Yeah it's a super hard problem, but my point is that in the specific case of a city building game most of the models are going to be extremely small on the screen 90% of the time, so you can get away with pretty terrible automated LOD in a way you can't in most other genres; you just don't swap to low-poly versions until stuff is extremely far away.
You're right, but you totally could make a game engine generate LOD levels for you. Especially for a game like this, where you could get away with a very crude LOD simplifier for tiny, distant objects.
In their case they can probably plug some open source library into their unity asset pipeline without much difficulty.
Honestly I'm just surprised they implemented so much complex stuff but didn't fix something so basic. Makes me wonder whether these blogs have correctly diagnosed the problem.
Yeah it's a super hard problem, but my point is that in the specific case of a city building game most of the models are going to be extremely small on the screen 90% of the time, so you can get away with pretty terrible automated LOD in a way you can't in most other genres; you just don't swap to low-poly versions until stuff is extremely far away.