A couple of things on LeBron, first, BOS could pay him more than a vet min contract if they wanted to. BOS can't give him anything close to Max money, which LAL could if they wanted to, but even giving LeBron $10M would be entirely workable for BOS.
As to hating BOS, I can't say how he really feels about that but he is part owner of Fenway Sports Group (as others have noted).
LeBron James is a partner and minority equity holder in Fenway Sports Group (FSG), the parent company of the Boston Red Sox, Liverpool FC, and the Pittsburgh Penguins. In 2023, James and his partner Maverick Carter increased their equity stake in FSG as part of a lifetime marketing deal, solidifying his role in the ownership group
As to LeBron the player/person, I hated the whole Decision hoopla, but I have softened my view of him over time. He could still really help the team in my view. I don't think he would be a cancer or anything like that. I don't see this as likely, and for sure only if BOS gets Giannis, but I would be thrilled if the BOS big 3 next season was Tatum, Giannis, LeBron.