On accessibility: I see more custom components that nobody cares to make it properly working with keyboard interaction compared to native HTML input components.
On standards - mixed feelings: we had XHTML, now we don’t. We had IE and jQuery to deal with it, now we don’t need it, but I still see many places that have the old “works best with” message, now with Chrome instead.
On maintainable code: it’s a different shit show, we exchanged spaghetti code for billions of npm dependencies that break if you dare to try and upgrade something.
For better or worse, we lost this capability in the path for code purity, RESTful services and SPAs.