Indeed. Most assets listed by OP (and are rightfully high quality) are essentially "patches" for unity's crappy engine.

When I asked for a good engine, ppl here would recommend Unity and Godot.

The difference seemed to be that Unity comes with everything out of the box and Godot, while free, would require you to "fight the engine" along the way to build a game.

In my experience, Unity felt free to play, pay to win. I felt that the engine was full of holes in stuff that I expect an engine to handle. It's not a small percentage of games that need controller support, or tilemaps, or proper sorting of sprites. Some of that eventually became officially supported by the engine but by that time I was more than happy with Godot.

I've seen people give 2 hour long talks about how they managed to force Unity to do pixel perfect rendering, while in Godot it's a couple of checkboxes.

So I guess it depends a lot on what you're trying to do. For some games Godot might not be the best choice and that's fine, you have to choose the right tool for each project.