We are now in a position to evaluate the impact of Covid vaccines. Overall, I believe they were a success, actually well beyond what most informed people probably anticipated in 2020.

Covid vaccination saved millions of lives globally. It didn't protect much from infection, but that could have been anticipated. Coronavirus infection itself only provides transient protection from reinfection (as does flu). The benefit is long-term memory B/T cell immunity.
Covid vaccines come with risks of adverse effects, as any vaccine, and any drug, and any medical intervention. Though, the rate of severe adverse effects of Covid mRNA is actually pretty low relative to most 'traditional vaccines'.

The benefit/cost ratio of vaccination in the most 'at risk' demographics was a no-brainer. That would have been the case even if Covid vaccine adverse effects were 100x higher.

A first exposure to Covid through vaccination is safer than through infection for everyone. That said, the relative benefit is much higher in older people and those otherwise more at risk.
For people who have been infected by SARS-CoV-2, the benefit of vaccination becomes less clearcut. Young, healthy people probably don't gain much, if anything, from additional vaccine doses at this stage.
I believe it was a major mistake to enforce Covid vaccine mandates anywhere. I also do not believe that the case for vaccinating healthy children and young adults was ever that clearcut.

We are seeing the resurgence of a massive anti-vaccine movement cherry-picking genuine cases of adverse Covid vaccine effects, and more generally making up some utter nonsense. This is highly regrettable and we may pay dearly for that in the future.
The anti-(Covid)-vaccine movement is largely driven by fools, grifters, cranks and frauds. The reasons why their often incoherent claims get so much traction are complex.
I believe the scientific community (in particular public health) shares some of the blame for this sorry situation, by often having pushed for vaccines mandates and having made fantastical and unscientific claims themselves, rather than sticking to the evidence.
I also regret the politicisation and at times atrocious messaging in favour of vaccines, in particular in the US.
Vaccines in the US should probably have been sold to the public as a product of American 'can do' spirit and enterprise. They could have been called 'freedom shots' and pushed with slogans such as:
"Get your shot,
Drop your mask,
Be a patriot,
... "
Anyway ...
And before anyone accuses me of being a 'Pharma-shill', I have no conflict of interest to declare here. I had zero research, or personal funding from industry over the last 10 years.

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A good thread on COVID vaccines, and a post-mortem as of now.