I use nova launcher. It allows you to replace any app icon by any png file. So you can download the old icons from the internet and use them on your phone. It's a lot of work and I agree Google shouldn't have done this, but at least you can revert it if you want to put in the effort.
Lol at the Photos icon. How does that in any way represent a photo or a camera? I guess it's an iris shutter but that's not something you notice too often on a real-life camera.
I think it's kinda morphed into a pinwheel, which still sorta makes sense as pinwheels have been a staple of photo and camera advertising for their bright colours and rapid movement.