This post bothers me.
For starters, COVID becoming endemic was never inevitable. From the word go, it has never been exclusively about individual action as you hint towards, but about governments doing what the fuck they're supposed to do: lockdowns, testing, proper regulations and mandates, and when they became available, widespread vaccination while maintaining all the regulations we have had up until this point. To underscore this, cases have gone down every time even when milquetoast lockdowns (as per the norm for the past year aside from Spring 2020) have been implemented.
By saying that the spread is never going to cease, it is effectively saying that, like the capitalist governments of the world are insisting on, that we 'need to live with the virus'. This has never been the case, and it still does not need to be - the majority of the world's population has not yet been infected, and governments could very well implement a Zero COVID strategy right now and still have success. The reason they won't is because they are driven by businesses to keep conditions favorable for making profits.
COVID will not disappear just because the US manages to vaccinate a good chunk of its population. This virus exists outside of the US: a very, very small portion of the world has been vaccinated, and with governments pursuing 'herd immunity' policies around the globe, a risk of a mutant variant that hampers the effectiveness of the current vaccines will remain present. Should one appear, it will make its way back to the US, and boom! Everything's back to square zero.
What now, you say? The working class needs to fight and underscore the criminality of capitalism and its role in this pandemic. Lives need to be protected, the idea that we 'have to live with the virus' needs to be blown wide open for the fraud that it is. Otherwise, we are letting them get away with doing this now and in the future; we are effectively covering up and enabling the criminal nature of capitalism and its role in this pandemic.
In the meantime, we do what needs to be done to protect our family and community. If that means wearing a mask and social distancing for a long time, so be it.
In addition to what's already been outlined in the OP and in the comments here: unless the majority of businesses, universities, eateries etc. require widespread proof of vaccination (and I have my doubts about that), what's stopping someone from not wearing their mask and saying that they were vaccinated? This is effectively ending the mask mandates across the country in a roundabout, underhanded manner.
Vaccinated people, especially in the US and UK, have since been used as a battering ram against any remaining measures in place so the economy can fully reopen and businesses can get back to uninterrupted generation of profits. Then once a variant that evades the current vaccines pops up because of the virus going unchecked elsewhere, they're going to play completely dumbfounded despite knowing full well this would happen.
Disgusting. Not unexpected, but disgusting all the same.