Bullshit because he might not join or bullshit just because bullshit ?
At least for me it makes sense. If you don't like a character then he would be a candidate for joining protagonist team and becoming one of main characters, you would hate that even more, wouldn't yet? I would at least. Although I'm neutral about Bellamy.
I want Aokiji to join them, but dreams…. dreams...
Bellamy can't join because he doesn't have a crew :ninja:
That's fine, Usopp disbanded his "great crew" for Luffy.
I can't quote Bellamy word by word as I don't read manga in English. However one of the reasons he wanted to be part of Dolffys family is that he could survive upcoming changes in New World. Now as Dolfy is not a role play for him anymore and obviously will be defeated by luffy, not much will hold him from joining luffy. He also might find a new dream or goal.