This is not, in any way, similar to thalidomide. Thalidomide was an issue because it is enantiomeric and different effects were caused by each enantiomer, only one of which was noticed. That is not an issue here, as we are talking about proteins. The primary difference though is that there was no treatment imperative with thalidomide, but there is with this.
Again, we are talking about introducing something that is guaranteed to be in your body anyway if you contract COVID-19. SARS-CoV-2 is viral to the point where, without perpetual lockdowns/mask-wearing/vaccinations, you will get it. So it is still definitely better to get vaccinated, at least with an mRNA vaccine – please stop spreading FUD. Your concerns could be more warranted for vaccines like J&J which use modified viral vectors, but again, exceedingly unlikely that this could be any worse than the virus itself.