Glad to see some discouragement of custom design systems. I shudder at the person-hours that have been squandered on that fruitless endeavor. Pre-web, essentially zero time was spent on "design systems", and we were all better for it.
Absolutely. The work of user experience research has a long history and is very important. What is new is every single "app" (website) inventing their own entire conventions and "language". This still happened with desktop apps, but it was rare typically limited to the largest players (Microsoft, Adobe). You can do a tremendous amount with basic, bog-standard, GUI widgets if you apply them well.
Part of the problem is that we just don’t have a std lib, or std UI framework for the web. In both Windows and Mac, the basic UI happy path involves using the pre-built libraries and UI components these companies created to make apps somewhat consistent. There is nothing like that for the web — which is part of what the article gets at.
Quite a few of them, yeah. jQuery UI was a huge, massively widespread thing for a while too.
People still do their own things of course. Like how tons of Windows apps build completely custom stuff (e.g. Winamp). Or very nearly every single videogame.