... and all the other apps, you can.
On our Monterey Macs we have older Outlook, Excel and Word, all still running fine but can't be updated.
With Teams, it's a different matter. At first (about 3 weeks ago) you were directed to the web version with no other option but if you immediately quit and went back in, it worked fine. Then you had to reboot the app (not the whole machine) twice... for a while. Then about six times, until now, when you can boot and quit the app 100 times you get the splash screen that says you can only use the web version. The actual version of Teams has not changed.
Fairly annoying seeing how much this company are paying MS to use all of this.
At the moment, if you take all traces of Teams 2 out, drop the old Teams Classic in the applications and boot it, you will get warnings and an option to 'switch' (which you can't because the OS is not supported) then the option to contunue using Classic Teams. Choose to continue using Classic Teams and it's up and running and functioning fine. So it is a deliberate block from MS.
How long this Teams Classic trick will last is anyones guess though.