There are only like three or four that aren't just flat buttons with a different border radius and colour. If this had been done in the mid 2000s it would have hundreds of entirely different looking buttons. Glassy buttons, metal buttons, glowing buttons, pixel art buttons, cartoon buttons, etc.

It's called design and thank god everything isn't the same.

Gtk has some nice standard looking buttons for you. You know how those look, and I'm pretty sure you don't want that.

Think to when "UI experts" impose edicts from top down, such as "flat design" or "material". Are you really happy about that?

The fact that we're even looking in awe at this list is amazing. If everything were the same, this wouldn't even be interesting.

This is fun and we need more of it in the world.