I opened my Bluesky account out of curiosity but my real audience are still in X. That's just the honest truth. A lot of people create profile there, post for two days then disappear. If your followers are not there, who exactly do you want to market to there? I still cross post because it doesn't cost me anything apart from time. One viral post could just happen anywhere these days. So, I wouldn't shut one door because another one is trending. I build everywhere gradually until one platform clearly starts bringing better conversations and traffic.