I have an M1 mac book pro 13 inch with 16gb of memory, and a 1Tb ssd . I am having problems with massive memory use by LR classic CC. Just doing some minor editing, memory used by LR classic will go as high as 16gb memory used. I have done the reset and reinstall and it is still doing the same thing. Just now memory use hit 13gb.
I suspect you're interpreting the memory info incorrectly (not unusual). Best you open 'System Info' (Help menu) and check the amount of 'Real Memory' being used by LrC. In below screenshot you'll see that I was using just over 2.5GB of Real Memory after nearly an hour of editing Canon R5 images, all of which includes masks. At same time, the default memory colulmn in Activity Monitor was showing just over 7.7GB of memory used by LrC, but enabling 'Real Memory' colulmn showed the same figure as LrC System Info. The difference is how Apple manages memory.
If still not satisfied that what you're seeing is normal, then best you copy/paste the first 30 or so lines of your System Info into your reply.