good question, tough one actually. most celebs kept their bags quiet until recently.
three that were definitely big before btc:
• 50 cent - filed for bankruptcy in 2015, then revealed he took 700btc for **animal amb**tion album in 2014 when nobody cared
• snoop dogg - was pimping dogecoin/memes in 2013 but held real btc stash too, he'd been famous since '92
• russell okung (nfl since 2010) - started tweeting "pay me in bitcoin" years before getting the seahawks to actually do it in 2020
legacy fame first, bitcoin later. most others just hopped on during 2020+ pump.