Depends on whether the antagonist government decides to subpoena the social network. Harder to do on a decentralized platform but still not impossible. Besides, there are ways to corollate posting and traffic patterns to the targeted account if they're really determined to find out who it is. That's why an anonymous account, only ever accessed via a VPN or Tor (only one or the other, it shouldn't be accessed via both) is the best way to do it... And be sure your VPN is trustworthy, like Mullvad or Proton VPN.