Well, if you are arguing that among the vaccinated only people who have had boosters should be allowed in indoor dining if they are more than x months out, at least your argument is consistent.
The rebuttal to that is at a certain point, though, we need to stop being concerned about cases. Everyone is going to be exposed to the virus. If you've been exposed once (whether naturally or through vaccine) you are less likely to develop a severe reaction the second time because the virus is no longer novel to your system. There is evidence that people who have had it and have had at least one dose of the vaccine afterwards are supercharged, so it's probably a good idea. But we need to move on from the idea that cases are a bad thing. The reason why it's a bad idea for someone who hasn't had it and hasn't had the vaccine to go into indoor dining is that they are more likely to die....but they are more likely to die for any reason (going to work for example) so it's sort of beside the point to the dining question.
The other thing to realize is that unless you are immunocompromised, elderly or are a caretaker of the foregoing, your booster is taking a shot out of the arm out of someone in the third world who could have used the first dose and that could have been used to prevent more mutations from arising in the third world. So bit of selfishness going on there to keep you "safe"
