Always use a VPN with Nostr, unless you want everyone to know your location.
Discussion
But this is a problem with all decentralized networks — LBRY/Odysee also suffer from this problem. So yeah, make sure to use a VPN or Tor when accessing Nostr or LBRY/Odysee or any other decentralized network.
nostr:note18zhy46qsed69u7crcfqrmkt66jh6l2th54jen870ukrzgu20cvsquduze5
This goes for any internet activity not on a VPN