I use an Apple Magic Mouse 2 when working from my home office. Recently I've experienced some serious sluggishness, but there's a few quick ways to address them.
Fingers crossed 🤞 this works as well for others with similar wireless mouse problems. (I have a Magic Trackpad as well, but I’ve never experienced sluggishness or stuttering when using that for input.)
The first lesson is to keep your mouse charged. Many reports of bad behavior relate to the device having a lower battery. Charge regularly and there's a good chance you'll be off to the races again.
If you use a mouse pad, make sure your hand position isn't keeping the mouse too near to the top edge of the mousepad. Passing over any edge/threshold (for some optical sensors) can create confusion and cursor stutter, though it really seems to stand out with the Magic Mouse.
And for the fun stuff: from a Lifewire article I came across, there's this:
There are a number of preference files related to the mouse that could be causing the problem. As a result, you can [...] get rid of all of them, and let your Mac rebuild the preferences.
The culprits we're looking for are located in your
~/Library/Preferences folder. You'll want to delete the following:
Reboot to rebuild them, and (hopefully!) enjoy a smooth and snappy magic mouse experience.
Again, more details at Lifewire for the curious.