Agreed. The library was just a dumping ground for apps that I didn’t want on the Home Screen and didn’t care how iOS organized them. Easiest way to get to them was swipe down and search.

Never used the iOS feature, only a categorized menu on Linux where the categories are curated by humans, but I always felt like having categories is mainly helpful for people who aren't as proficient with computers.

Like, yeah, when I want to create document, I'll type the first few letters of "LibreOffice" and that's much quicker. Even on my phone, I'm using a search-based launcher, because often just the first letter narrows it down enough.

But my parents, they can't remember that it's called LibreOffice. I mean, it would probably still show up, if they'd search for "document" or "write", but they don't really think to do that.
They do want a list of everything that's there to just click through and having rough categories does help them find it more quickly, particularly because they don't even necessarily recognize it when they'd find it in a big list. The category reassures them that it is what they're looking for.