Nah it's over.
They need a legit all-star and they don't have pieces to make such trade. Sure sometimes there is some sucker to give their star away for smaller return, but I don't think it's happening this time.
2022 was a perfect situation for them take one more trophy and they did it, by beating opponents with experience. Grizzlies did not have a winner's mentality + injuries, the Mavs in conference finals were also too inexperienced and mentally they felt like they already achieved their goals by upsetting Phoenix Suns. And in the finals once again Warriors showed they had far more experience in that environment than Celtics.
It is what it is. It's a result of aging players and bad drafting like that totally wasted pick on James fukking Wiseman. That 2nd overall pick could have landed them a proven player in trade market.