The mask does not protect you from other people it simply reduces the risk of someone passing the virus along to someone else by droplet contamination. Far more likely to have picked this up by some inconsiderate fecker coughing on something you have touched.
I'm in my 60's now and am not only vaccinated but have had 3 'boosters' but I still attempt to maintain my distance from others (not easy in a shop queue) and find my normal cough as a committed smoker (for 45yrs) makes them give me a bit of space.
Not quite true any mask is of some use cloth or basic surgical type will have some limited protection for the wearer and better than nothing. Respirator type (FFP2/3 or N95) are however effective at protecting the wearer. Only this week The Royal Society paper on ranking effective covid measures ( the 1st to do a true evaluation of measures) put mask wearing at 3 on the list. Fomite transmission of covid is pretty much a dead duck as with any airborne disease is the least of your worries. The RS paper had it way down on the list.