This thread...

One thing about the mirror that should be added: Normal mirrors are stereoscopic. Each of your eyes gets a different refraction angle because your eyes are at slightly different angles to the mirror- which means things you see in the mirror are "3D" by your perspective, since your brain is used to resolving both eyes getting an image from slightly different angles into actual depth perception and spatial relationships.

An LCD screen is flat, excepting 3D goggles or technology like the 3DS screen. No wonder it gives you simulation sickness.

That was a nightmare read. I would have taken one look at that mirror and told the rental company I need a different car.
There's also the distance between our eyes, the mirror, and the length of the car that we drive that also play an important subconscious role in determining depth perception of the cars in our FOV behind us. This is something you just can't replicate with a camera as it is fixed in one location that you're not accustomed to.
We get used to this feeling quickly, even when driving rental cars that aren't our own. Then our brain adapts to it and we're all good.

have any SUV with this type of rearview mirror and honestly IMO it is the best driver assistive technological in a decade, in actual mirror mode I get a small view around 400 x 400 mm but in camera mode I get a full unobstructed view. I get the complaint about VR sickness as I had a few existential crisis's when the vehicle was new but that issue passes with time and it is only an issue for people who have muscle memory that the rearview is a mirror, as this option becomes more popular younger generations won't be affected by this.

I agree. Too many benefits. It’s basically a permanent reverse camera.
Wider FOV.
Muted maximum brightness (no more being blinded by headlights).
Night vision and other darkness assisted vision.
No issues with rear window size, design, luggage, and passengers.
If positioned well, camera is much less likely to ice over than rear window, and won’t suffer from being fogged up like a rear view window.
- The only issue I would have with something like this is the same issue I have with backup cameras (which I can't live without anymore) is the visibility obstruction caused by condensation or precipitation. I'm in the Midwest and I regularly have my backup camera partially obstructed by water droplets or entirely covered by snow. I've had instances where I clean it before leaving and it's obstructed by the time I get to my destination, so I'd be worried about losing the camera mirror the same way. Won't be a big issue with a physical mirror, but still annoying.

I feel like the rear windows keep getting smaller. Is it for crash safety? It's hard to see out of with the mirror or by turning your head to look. I used to laugh at people that couldn't reverse but I drove a family member's CUV and couldn't reverse that damn thing the sight lines were so bad.

Cabs are getting bigger (without expanding cargo space) which means the window might just be farther away with more awkward sight lines.
Cars are enshittifying.

This came as a feature buried in an option package on a car we recently bought - we'd almost not noticed it had it. (It's off by default)

I decided to try it. For about an hour I didn't like it. Now it's the only mode I use. (mostly) My observations:

General:

I feel very, very sure that no one is selling this feature without the ability to turn it off currently. I could be wrong, but I feel very, very sure.
Spend the three minutes to adjust it to your preferences if yours has those options. (zoom, etc) It makes a difference.
Person in OP could probably spend 15 seconds looking at the back of the car to find out where the camera is.
Another comment in the thread makes the point about 3D. They are correct but I find it doesn't seem to make a real difference in practice, for me. YMMV.

Pros:

Doesn't matter who or what what is in your back seat or cargo area. You can see behind you.
Vastly superior at night - light gathering, like when you look through binoculars
Makes you immune to "guy right behind me is in a lifted truck with high beams on"
For the most part I don't find a problem judging distances, after a period of adjustment. It's not your back up cam - which any car with such a mirror surely has. And you should be turning around when you back anyway, and/or you can flip the mirror to normal mode.

Cons:

For those last couple of feet, where someone is pulling up behind you at a red light, that's the case where distances are way off. It feels like their front wheels should be inside your car. When someone pulls up to stop behind you in such a circumstance, this is visually alarming until you get used to it.
I wear reading glasses. Through some process of how your eyes work that I can't explain well, looking through a mirror at a distant object is apparently like focusing on that distant object. So my glasses never came into play. But looking at a small screen 18 inches from your eyes is looking at a small screen 18 inches from your eyes, and sometimes I have to push my glasses up to be able to get a good feel for what I'm seeing there.

Overall I like it more than I don't, but I could see how some would feel differently.

For the zoom, I set mine to mostly match the physical mirror. The downside is it's a bit lower quality (digital zoom), but having the wider field of view is a con to me. This way, I get all of the pros you mentioned, without the weird positional con.

One wonders what problem the manufacturer thought they were solving. This is a classic example of a high tech solution that is way worse than the non-tech original.

They were solving the issue where people overload their trunk and can't see shit from their rearview mirror. It's still a mirror usually, there's a button to turn off the screen and use it normally.

Any idea what car?

Jeep Grand Cherokee

I’ve seen new Nissans with this but the mirror also is an actual mirror. Just if you flip it down to night mode (aka fuck why are your lights so bright it hurts mode), it turns on the camera instead. So you have a choice of mirror or screen. Wondering if that was the case here and this person just… can’t figure out anything. Seems they couldn’t figure out how to like hit a few buttons to set up main screen so idk.

I'm pretty happy with my backup camera...I often don't even use the mirrors... It takes a bit of getting used to though

I think OP is about cars where the rear view mirror is replaced with a video feed instead.

Working in automotive development I've had some experience with these. You can get used to it pretty quickly, to the point where I was able to do a test of a simulated reverse AEB and consistently come within a few centimeters if the target.

Additionally, a lot of these can be turned off and used as a mirror.

Would I prefer a better 'greenhouse'/better visibility? Yeah, but that's not going to happen anytime soon. It's a separate discussion but one I wish the auto industry was having more

I've been using the rear view camera on my Tesla exclusively ever since I got it. It does take some getting used to but it works really well. And if you look into rear view mirror while reversing, you have no business driving a car anyway.