mouse lag

Wow, what an unhelpful response. First Aid and New User files? jdo_apple didn't even try.

Noly_Binay, not sure if you're still having this issue, but it seems to be that the polling rate on the Logitech mice is more than Big Sur can handle. I think your G-series mouse has the ability to change the polling rate via the mouse options software Logitech provides for the G-Series gaming mice (set it to 125MHZ, if you can). Allegedly it also will help if you reset your Bluetooth connection on your Mac, and remove any out-of-date Logitech software that might be trying to manage the mouse.

Hopefully, they'll have fixed this larger issue by the time they release 11.1.1/11.2, but that could be months away.

Sorry the guy above was going for fake internet points instead of actually trying to help. I understand how frustrating that can be.

Hello Noly_Binay,

Thanks for that info and for choosing the Apple Support Communities. If we understand correctly, you are having an issue with your Logitech mouse and your Mac after updating to macOS Big Sur. First, try running First Aid on your hard drive with the built in Disk Utility tool, as this can correct simple issues like you're experiencing.

Disk Utility for Mac: Repair a disk using Disk Utility

You can figure out if unexpected behavior is related to a user file or setting by trying to reproduce the issue from another user account. This process includes creating a new user account, logging in to it, and testing for the issue.

Set up users, guests, and groups on Mac

Cheers!