I recently picked up this rabbit hole of a hobby. It's only when you want to get fancy, and have lots of mismatched stuff, that it gets that complicated. (Which, as nerds, we are wont to do.) If you just buy into one brands stuff, and use just that, you don't get lost in the home assistant quagmire. There are quirks, eg Phillips Hue has a 50 device limit per hub resulting in needing multiple hubs for a complex scene, but it works for people who aren't programmers.
Meanwhile, as a hardware hacker and software engineer, yeah, I'll admit, I had to do things that look a lot like my job I'm paid very well to do in order to get my light switches to work right. No idea how people who don't program for a living are supposed to get Home Assistant to work quite right!