Whatever mask one wears is fine by me. They are primarily to suppress your droplets from being sprayed upon another, as you speak, cough, laugh, etc.
To protect yourself from inhalation, you need proper fit, proper filtering and more protection that just ones nose and mouth. Then, presuming the infection has been contained to the exterior of the device, removal and sanitation, to avoid contamination, are critical.
Hugely complex to protect oneself, better if everyone just kept their own germs to themselves.
The main thing is FIT. I see masks every day with gaps on the bridge of the nose, gaps under the jar bone, and riding too far down. This can result from a mask that is too large, too small, improperly adjusted, or just a poor design. The ear loop designs are easy, but around the head 2 places is the industry standard for a reason; the fit is more secure.
Yesterday I was sailing with a friend. While working engine we masked; impossible to maintain any distance. Once we got out and the wind picked up, we didn't since on a multihull we stay far apart anyway. When we returned to the dock, I sent my buddy home while I tiddied up; it's not a 2-person job, not really.
As others have said, it's mostly about others. This sums it up very nicely. Keep your own pee... so to speak.