These changes aren't made in a vacuum. Big companies with mature products base them on user research and data. If you dislike switches, that's entirely your right, but you are likely part of a minority.

There are many advantages to the new preferences UI. My top two:
1. Being similar to iOS means macs are more accessible to people who have already seen something similar on a phone. They don't have to learn something new.
2. The old UI is just a big grid. It's useless if you need to look for something specific unless you’ve memorized the grid and know where every item is. And then you change the size of the window, and everything is suddenly somewhere else. It's easier to go over a list than to figure out where something is in a grid.