This guy makes sense. He reviewed the UK data and has some interesting conclusions.
https://www.youtube.com/c/Merogenomics
His biggest concern is that the spike protein has the potential to enter the nucleus and affect the DNA replication process. Not good if true.
And it may take years before we know for certain that it is not an issue. Apparently, when the vaccine was designed it used the whole spike protein instead of the small section that interacts with the cell membrane. The small piece spike protein is sufficient.
We really don’t know long term safety.