See these peer-reviewed papers for some insight into the second and third order evolutionary dynamics that we face with the current spike protein focused mRNA vaccines for SARS-CoV-2 [1][2].

These are serious long-term concerns, which may not manifest overnight, but they are certainly on the radar of many experts in the field.

[1] Risk of rapid evolutionary escape from biomedical interventions targeting SARS-CoV-2 spike protein https://pubmed.ncbi.nlm.nih.gov/33909660/

[2] SARS-CoV-2 immune evasion by the B.1.427/B.1.429 variant of concern https://science.sciencemag.org/content/early/2021/06/30/scie...

[3] Imperfect Vaccination Can Enhance the Transmission of Highly Virulent Pathogens https://journals.plos.org/plosbiology/article?id=10.1371%2Fj...

On websites where covid vax hesitancy is rampant, I often see posts discussing antibody mediated enhancement, vascular damage caused by circulating spike protein increasing vascular damage and causing death from heart attack and stroke in a few years, prion disease development from misfolded protein propagation, and fertility issues. For most of these issues, long term data is needed to rule them out.

Over a long period of time anything is possible.