They will never piece it together.

I have also made a similar hypothesis. That if there are widespread longer term side effects, I call it "vaccine disease" that begin to pile up, the vaccinate will HATE the unvaccinated more than we can even imagine. You think they hate them now? The resentment for having their hero status stripped from them will be infuriating. So many already get furious when they are informed that they can spread the disease just as effectively as the unvaccinated. That they are really only protecting themselves.

If huge swaths start getting horrific problems after having 'done their part' and became self appointed heroes they will go apeshit. To be punished for blinding 'doing the right thing'.

Some will go the other way and will become automatic antivaxxers for life. I'm not antivax, never have been, but I really don't like rushed 'skip 7 years of standard safety' medication. I might even get the ultra traditional Novavax when it comes out since it doesn't use the dangerous COVID protein spike.

But the people who have 'vaccine disease' will be so damn angry and they won't like having their moral superiority over the antivaxxers suddenly stripped away from them. I can see exactly what you are saying happening.