As I said, no one (or at least no competent medical professional) ever said that the vaccinations would be 100% effective.
Dude, you're the one bringing 100% into the discussion. The original claim from both Pfizer and Moderna (and backed by public health authorities as well as enforced by social media) was ~95% effective. If they had been 95% effective at preventing infection and retransmission and also provided good protection for the remaining 5% of breakthrough cases then I'd say the critics of the inoculation would have less to complain about.
Those same people also were quite clear in saying that there was absolutely NO guarantee of what would happen to the vaccine's effectiveness once the virus began to mutate, AND they were quite clear in warning that the virus WOULD mutate and would very likely mutate rather quickly (which it did) because that is what viri do.
No, that was not a clear line of messaging in the early periods. In fact, I don't remember any significant messaging about that until well after variants starting popping up. I'd note that if you know your inoculation does not provide near sterilizing immunity then it is going to produce selection pressure in favor of inoculation-resistant strains.
So if, as you claim, there was a general understanding from the public health community that the virus was likely to mutate quickly, and that the inoculation is not going to provide sufficient immunity to wipe out the virus, then the mass-inoculation effort must have been engineered to fail. Under those conditions, and knowing as we did that the disease disproportionately impacts people based on weight, age, and general health, the correct action would have been to deny vaccination to young and healthy and to provide it exclusively to the elderly, the obese, and the immunocompromised. Injecting young and healthy people - who are unlikely to have a serious expression of the disease anyway - is simply going to speed run the virus' development of inoculation resistance.
The only people I saw claiming that the shots would be 100% effective were idiots in the media who were hyping the "gotta do it to protect everyone and stop the virus in its tracks" line of though (which did come from health professionals and the government) and anti-vaxxers who used the 100% claim as a point of failure to weaponize their anti-vax status.
Again, the claim was 95%. Made by media, government, doctors, researchers, pharmaceutical manufacturers, and really the only line that could be spoken in polite company. Claims against the 95% effectiveness were considered "vaccine disinformation". "Breakthrough cases" were supposed to be rare.
We were sold the line that if only enough people got the inoculation the virus could be eliminated entirely. That is only possible if it provides significant protection against both infection and retransmission - not just protection against the worst of the consequences when you inevitably do get infected.
For some reason I thought were old enough to remember this...