That's your choice, but what about my choice? My doctors are no longer doctors, lawyers are in control of my healthcare now. And if my doctor insists that I wear a stupid mask and increase my intake of co2 when my saturation levels are in the mid 70's without extra o2 I am pissed and he should not expect me to be a happy camper.A mask will NOT prevent you from catching Covid. The only thing that would be close to 100% is a PAPR hood.
I use a 3 layer mask that has an insert pocket where I place FILTI which is about 90% by itself. With the additional layers it should be above N95 level protection. I don't worry about myself, but my youngest son gets things very easily and had breathing issues as a baby.