Super slow wifi on Mac mini M1

Seems to be a recurring problem, is there a fix? Can't believe a brand like Apple could have such blatant problems.

I have a high speed 5G internet connection. But in my study, my Mac mini M1 (OS 12.3) drops to between 5 to 30 Mbps, which constant and huge variations.

If I put my MacBook Air right next to it, or my phone, I get 5 times that amount. Again, exactly in the same place. The problem is not the router, the distance, it's the Mac mini 1. See picture (and I was lucky to get 32 on the Mini, it's usually lower).

What's going on? Is there a fix? I don't have to have a Mac in my study so am very close to selling for something that works.