If you live in a state where dissent is violently opposed, you have a legitimate grievance and you or your family are at risk, then yes, crack on, wear a mask.
Do what you need to do.
If not, then the majority, no matter how much they agree, will dismiss you as a poseur.
The people who ruin legitimate protest in this country are the anonymous, violent minority who attach themselves to perfectly rational causes.
Anonymity leaves us open to infiltration by those we oppose.
There have been countless marches and demonstrations in this country where the first bottles and rocks were thrown by unidentifiable people who subsequently just melt away, leaving the unmasked to deal with the consequences.
Who were they?
Who’s side were they on?
Who incentivised them to act as they did?
No idea, they were anonymous.