This is one thing I like about Android. In developer settings you can make every UI animation twice as fast or even turn them off entirely. It's the first thing I do on every device I use.
I think animations are fine and even good as long as they're communicating something to the user (not just done for flare) and perhaps more critically, are non-blocking (e.g. the UI is still functional during the animation) which makes the ability to toggle off animations less necessary.
Switching spaces on macOS is one of the best examples of easy improvements. There's info being communicated (where the user is being swept away to, where the destination desktop sits in relation to the current one) but it should probably be sped up by at least 40% and not block user interaction so if there's a focused textfield at the destination desktop, the user can start typing mid-transition and no text will be lost.
Yeah, UI animations can be good. The vast majority are bad, and even the good ones are almost always too long. That's why it's nice to have a setting for them. Those macOS animations you mentioned have no settings to make them faster and they are infuriating.
On phones I usually speed animations up rather than turning them off entirely. But on the Pixel Watch the animations are so gratuitous and add so much friction to my use of the watch that I turn them off entirely.
I haven't tried a Pixel Watch, but on phones I find Android animations generally kind of awkward. They too often feel like they don't fully connect with what they're animating, if that makes sense, and the curves they're on are often odd. I could definitely see the appeal in turning them off.
