Why do people call them muzzles? It’s just a face mask.
Probably think it's edgy and witty.
I don't go with the muzzles thing at all myself, but thinking objectively, I do think people have the right to their own peaceful angle and response to government actions and requirements, if they personally believe something to be unreasonable/tyranny/spin/sexing up/doublespeak/ulterior motives or whatever.
There were some DM readers people who ridiculed those describing the 'under-occupancy penalty' as a 'bedroom tax'; also, there are various official 'equality and diversity' umbrella policies which throw women's rights under the bus, and thus those concerned about this refuse to use the official terminology.
As long as people don't break the law, I don't see any issue with them peacefully protesting in their personal interpretation and opinion of government policy, even if the majority disagree and don't see any issues with it. Dial it back far enough and there were people slapping down the women 'going on about' the government lists headed something like 'all eligible voters of sufficient age' which only actually had half of the names on there that they should have done.
Some principles are crucially important, some are frivolous, many are somewhere in between; but people still have a right to hold them, regardless.