As a former polyamoric person, here's how I (still) think of it:
You can't control your feelings (they are merely physical reactions to situations) but you can control how you deal with them. Or how you act on them.
So in a sense, in my opinion, you're both correct.
The point is, it has to be reproducible. On a clean FF install on linux, I cannot replicate this. Changing user agent does not affect the page load speed. So there has to be some another aspect, maybe iser's OS configuration or smth that affects this, too.
I'm a lot like you in a way, and I agree with what you said, but I just wanted to note that you are NOT invulnerable to marketing or ads. Advertisement (brainwashing) techniques have been researched for centuries, and with massive resources. I think even the very thing where some people think they can't be affected by marketing, is a marketing technique itself. Probably.
The horse is already dead.