My personal experience with Win11 is that it is definitely slower and less snappy than Win10; be it on older hardware and even on brand new hardware.
I'm not sure how they messed up the GUI on Win11 so much to have a sluggish right click, an even slower "Win + space bar" (instant on Win10, takes 1 second on Win11, which might not seem like much, but... it's just ridiculous how slow it is), and add to that that, things that used to take a couple clicks now take a ton of clicks.
I'll install Win11 on my Framework Desktop when it arrives because there might be things that will only work on Windows... but I'm going to dual boot it with Bazitte and will probably use that as my main OS.
Win11 is just a terrible disaster of an OS.