That's the interesting question, isn't it? I DO like D&D. I like mechanics, I like fiddling around with character builds, even though actual challenge at the table isn't a major priority. I like plenty of games MORE, but D&D is fairly easy and has a lot of material, which is fun.
It helps that more of my tables are slowly converting away from 5e, so it doesn't feel quite as overwhelming.
But yea, 5e has some solidity to it, which is nice, but it's still easy to reskin and get into a form I want, which makes it good for shambolic hangout games I end up in quite a bit. And everyone already knows it.