Yes, I googled it and indeed found a paper about neutropenia being sometimes observed within 7-14 following vaccinations in general. But if this is what's behind the entire argumentation against covid vaccine, then the reasoning is moot since CDC considers people to be fully vaccinated only two weeks after the 2nd shot, and advises people to behave as if they were unvaccinated before that. So people "walking around and getting infected" within 14 days is a problem created by people's behavior, not by the vaccine. Of course the other important point is to know if unvaccinated people that get infected by covid also develop neutropenia and lymphocytopenia.