Another thing that's pretty interesting to have, but isn't quite there yet is dynamic render resolution scaling, which can be a godsend for lower spec devices.

That said, there's pretty much nothing preventing from people writing their own functionality to achieve this and someone actually did: https://godotengine.org/asset-library/asset/1141

(note: for some, certain limitations might be dealbreakers, as described at the bottom of the description)

It's pretty cool to see people creating pieces of functionality like this, be it terrain functionality, or even the resolution scaling, which you can see a video of here: https://www.youtube.com/watch?v=AW0A-G5mMcw

I also recall there being a more static version that didn't seem to mess with your scene (as much?), but it wasn't really suitable for dynamic resolution changes at runtime back when I checked.

Now if Godot 3 could get a backport of dynamic LOD that would be great, but other than that Godot 4 is promising and it feels like the engine has a bright future ahead of it!

I just doubt that the asset/plugin situation will get anywhere close to as much of a flourishing ecosystem as Unity's, given that the financial incentives aren't quite there yet. Of course, having most of the current ones (even if a limited selection) be free is nice, though.