According to these user reports, it seems that macOS Monterey has a memory leak bug. This has resulted in a variety of applications consuming abnormally huge amounts of RAM. For example, some users have found that Control Center is eating as much as 26GB of RAM, while some users are experiencing issues with Firefox, with some users also experiencing memory leak with the Calendar application.
Given that this seems to be affecting a variety of Apple’s Mac computers, it seems like this isn’t specific to any particular Apple computer. Users are reporting that restarting the computer does make the problem go away, but it eventually comes back. Apple hasn’t said anything yet about the issue but hopefully they are aware of it.
In the meantime, if you haven’t updated to macOS Monterey yet, then maybe it might be a good idea to hold off from doing so until Apple issues a fix for this problem.