The obvious reason, IMO too obvious to state, why infants don't wear masks is because they could be suffocated or strangled by them.
Yes...and there's also been a lack of understanding about transmission of the disease, back when the focus was not catching it. Initially, kids of all ages were given a basic 'Free Pass', simply because they didn't seem to catch it, end up in hospital and die.
The (not small) detail that they could carry it and pass it on was either missed or ignored.
For infants, there were plenty of cases where babies caught it (and sadly died), but the numbers didn't merit reporting in the general media and, compared to the masses who were dying, it appeared that the odds weren't worth worrying about. There were many households I visited where the whole family tested positive, including the baby, but not all got the disease bad. I also know of some families where Gran and Grandad took on baby care, as soon as restrictions were lifted and then caught it from the little one. That was all so sad when they then died as a consequence.
Babies also don't tend to travel as widely as their older family members and creating a suitably sized mask for a baby, that couldn't be pulled off, just would not work...no matter how closely a parent watched their child.
Even many adults seem incapable of learning how to wear a mask and seem content simply to stick one in the vicinity of the face, because they're supposed to.
@Naughts is quite correct with "Wearing a mask stops
you passing on the virus
so easily, but wearing one doesn't stop you catching it." (My italics).
No mask, test or vaccine is infallible, but all are undisputedly good tools to employ to try and curb the spread of the thing.
Last Christmas, when Joe and Josephine Public demanded that Christmas was a Right and that Christmas simply HAD to involve social gatherings,
, the cases shot up. Last summer, (2020), when the glorious weather arrived and some restrictions were lifted, everyone then rushed ahead as if we were 'back to normal', with crowded beaches and tourist hotspots...and guess what? Cases shot up.
Each time restrictions have been eased, the general public demonstrates its inability to behave in a mature and responsible manner and goes to excess, with cases going up yet again.
Meanwhile, back in the NHS, we have staffed who have worked solid since the Spring of 2020, skipping holidays and even days off, to now care for those who genuinely believe that a foreign holiday is a 'right', that mask wearing is unnecessary and all of those qualified experts are talking rubbish. (I always find it interesting when talking to the deniers in hospital, that all of them didn't do much science in school and prefer to trust social media 'experts' over real ones).
There is not a single person on this forum who is an expert on Covid which makes my opinion as valid as any.
No...it doesn't.
At a road traffic accident, for example, I know exactly what to do and in what order to do it. I don't have to be an expert, but unless you are also trained in serious First Aid and crisis management, your opinion is not more valid than mine. Too many times I've had to take a seriously deep breath whilst some self-entitled idiot was convinced that their opinion regarding the treatment was valid, simply because that was what they'd been taught from Day One at school.
From a starting point of basic medical training, enhanced with previous qualifications in microbiology, my own knowledge has been multiplied by those dedicated hospital specialists and unpleasant experience. No-one, not even an 'expert', will claim to be an expert, but there's no way your basic and unqualified opinion is as valid.