the collection of arguments being made by the protesters (as reported) mostly seem farcical and incoherent, but we should very much support their right to protest and challenge the authoritarian-prone position that we must be locked down indefinitely to beat this pandemic.
administrative directives need to convince a (super-)majority of the populace with evidence to gain trust and compliance. antagonistic pressure needs to remain so that the implied force behind those directives are removed as soon as possible (no sooner, no later).
An interesting aspect: Protesting a law should be possible without disobeying it. But the usual mass gatherings are kind of a problem in this specific situation.
Thus how to protest responsibly?
Holding a "Its just a Flu" poster while wearing a face mask might not be that ridiculous after all.
it's not clear that these protesters are being unlawful by disobeying rules implemented via emergency powers rather than legislation. while there's force of law behind emergency powers, it's not concrete who might be harmed by the protesters (other than themselves, and they're unlikely to sue each other given the nature of the protest).
with that said, yes, it's prudent to wear a mask around random strangers in close proximity while shouting (spitting) a lot, to keep from infecting each other. note that the flu is deadly too (30-60K/yr in the US), we just don't shut down the economy for it.
administrative directives need to convince a (super-)majority of the populace with evidence to gain trust and compliance. antagonistic pressure needs to remain so that the implied force behind those directives are removed as soon as possible (no sooner, no later).