You can completely disable animations in accessibility settings.

Do you mean "Reduce Motion" under Display?

Don't have an iphone handy but I think so. There are lots of options there to explore, there's also one to increase contrast and another to make buttons more evident. There's some cool stuff there in accessibility options

Ah, when "Mac" was mentioned I assume we were talking about MacOS, not iOS.

There is still a slow cross fade animation.