Airdrop stopped working? Never had such a problem with my Mac. Maybe the problem is that your device is already old. However, I still think it is not hopeless, if you read https://setapp.com/ that I found for you. This article is exactly about your problem. So if you fail to solve it, it means that either your IQ it too low, of the device is too old.

My experience is bad. Airdrop stopped working after the update. And whomever I try to complain, try to get rid of me the quickest. Why do you think this is happening?

In my opinion no. The fundamentals of OS X aka macOS have not changed significantly since 10.3. features that were slow in old versions are still slow in the newest new. But you should know how to do clean install macos monterey correctly. This guide will help you to succeed and improve your computer performance.

No. It’s mostly only Windows PCs that suffers from that kinda degradation - mostly. I’m currently replying to your question on a MacBook Air 2017 and I will definitely upgrade from Big Sur to Monterey because I want all the new functions.