If the virus could persist viably on surfaces, handling a soiled mask properly would be absolutely critical to getting any benefit from it, and handling it improperly would be risky. People wiped down their groceries for the same reason.
With the benefit of real data, we now know that touch is a negligible vector. The novel coronavirus does not persist viably for long on any surface. So masks are an excellent trade off.
That's not a reason to tell people that masks don't work. It's a reason to tell people that masks do work, provided you take precautions A, B, and C. And you should also say why those precautions are necessary--because of the assumed risk of touch transmission--so people can apply common sense, since no amount of advice from a central authority can possibly cover all individual cases.
You should probably look up dang's statements about this sentiment because its pretty funny how frequently this gets dragged out from literally anyone who feels disagreed with and hes got a nice rant about it.
It was always known, even prior to COVID and by the WHO (who posted as much on their website), that coronaviruses spread via respiratory droplets and that's what most masks are effective at protecting against.