For the record, it's not what "I know." I'm just a data analyst. Rather, it's what epidemiologists are saying after analyzation of what troves of data from all over the world has shown. Particularly from the areas where the more troublesome variants have originated.
I'm not sure I'm following you on how it can be detrimental, can you unpack that a bit? I mean, at some point, yes, there could be a variant that can evade the antibodies that the vaccine currently provides (which is when a newly programmed booster would need to be added to the regimen), but worst case, you'd get infected by that strain (just like the flu shot can't protect from all strains because they are constantly changing). Meaning the vaccine would be useless against that particular variant. But it's still effective against the other variants. Are you suggesting that the vaccine, when it meets the new variant that it's not programmed for, would harm your body?