UI/UX keep getting shittier over time is an industry wide phenomenon not a Google exclusive one. To me everything kinda peaked in late 2000's and has been on a downwards slope ever since the mobile became the dominant platform so everything from desktop PCs to cars had to look and function like a phone.
Perhaps controversial but I think the ability to ship continuously is also a factor. You just have to pass and fix the things with the most complaints after. A holistic view on the general user experience will never make it to the top of a pile now.
I think yearly releases were much better. I feel a lot of sites and software now have constant change you can’t keep up with and often the change doesn’t really improve anything. Reddit would be a good example. I constantly have buttons disappear and rep appear or move around. Same in YouTube. Much friction for no benefit.
