Earlier quoted context omitted.
Note that it appears that it is still unknown how likely breakthrough infections are to result in long Covid. The very limited data that does exist indicates that the likelyhood is rather high (~20%). https://www.nytimes.com/2021/08/16/well/live/vaccine-long-co...
Isn't long Covid caused by damage from the spike proteins? In that case, repeatedly giving people the vaccine might do damage as well since it gets you to produce those spike proteins right?
This article[1] says the cause of long covid is still not clear.