So you think that google is unbiased?

From all that I have seen and heard its at best split or the impact is so small that it is not noticeable. I think most of the ones that say it worked involved healthcare setting where trained people used good masks, not me at home depot with a mask from a box.

From your own source: 'Ninety-one per cent of observational studies were at ‘critical’ risk of bias (ROB) in at least one domain, often failing to separate the effects of masks from concurrent interventions.'

The whole "masks don't work at all" argument is pretty much still a strawman argument, because the actually good criticism was for mask mandates. Can masks work, if you use them correctly (don't touch them more than you have to, don't use one mask for too long and do not have a beard when it comes to n95, change them frequently when it comes to the other ones)? sure they can. Can mask mandates work, if everybody adheres to the rules and uses them correctly? probably, yes. do we have any reason to assume that everybody will do it that way? not really, no.

so my assumption and criticism was always: masks may work, when used correctly. mask mandates do not get people to use masks correctly, rather than just mandate to have some piece of cloth over your mouth, which you may have used for the last 3 months, at which point they do not really do anything anymore and may even become a public health issue in themselves.

so mask mandates are annoying as shit, don't do much to prevent spread and even have the potential to do more harm than good. if you can find a study that actually is able to isolate the effects of mask usage from other interventions, I'm happy to look at it, too.

even the German government classified the effectiveness of their own mask mandates as controversial in the official committee.

I get why bashing conservative anti-intellectualism can be fun and I can only assume that there were lots of idiotic arguments made against mask mandates, but it's actually not that easy.