@Lunar567, the most recent thing you posted:
evidencenotfear.com/masks-dont-work-a-review-of-science-relevant-to-covid-19-social-policy-researchgate/
has been taken down from both the places it appeared, no doubt for being more of the conspiracy theory stuff you've referenced before. Maybe this has run its course for you now, because it doesn't feel like any of the comments have induced you to rethink your position. Sorry about that.
@MedSchoolRat While you yourself might not have heard of the precautionary principle since 2001 and your negative encounter with an American policy maker, given your username, perhaps you'll also understand you're conflating absence of evidence and evidence of absence by assuming your own lack of knowledge means it's not widely known and accepted in some areas of medicine? A simple search of any of the medpub databases shows that's not the case: www.ncbi.nlm.nih.gov/pmc/articles/PMC4935673/
I think Trish Greenhalgh was making the points the way she did in part because of the tendency of anti-maskers to say there is no point wearing them because there are no controlled (ie comparison group) studies of masks vs non-masks. One of her points is that it is not ethical or necessary to use control group studies as the only scientific justification for masks. Greenhalgh is an experienced researcher and medic with an very strong google scholar profile and the profile of the guy you linked to doesn't match up to hers at all:
scholar.google.com/citations?user=yQbqigMAAAAJ&hl=en&oi=ao
vs
scholar.google.com/citations?user=8KQwEGcAAAAJ&hl=en&oi=ao
Or to save you clicking, there are 61,000+ citations to her work vs 900+ for his and other measures suggest her work is much more impactful than his also.
In the rare occasion/field where a woman is one of the established experts, isn't it a good thing, on mumsnet, for us not to promote/advertise the sometimes shouty men who talk over women, or even polite men (I'm not on twitter so I don't know about him other than the couple of "I know best about stats" tweets I just read below the one you linked), without at least pointing out the disparity in scientific achievements and recognizing scientific achievement and expert status? I don't mean renowned scientists shouldn't ever be challenged, but come on with linking to tweets/opinions, not studies.
Anyway, back to the topic of the thread, the overwhelming preponderance of evidence, opinion and common sense suggests masks, amongst other measures, are sensible precautions to take and the wisdom of mumsnet on this thread has shown the OP's question was one worth debating. I
'm not sure we've got to the heart of OPs question, which is, I think, that some can afford N-95s, some can afford healthcare standard visors too, and others have to make their own masks from socks, and is this equality?
The medical research on N-95 level masks, even in non-medical settings vs surgical/cloth etc might be looked at... Is this inequality? In my opinion, yes. There is also the issue of valved masks...
Me, I'm holding out for a vaccine.