No, you don't need a VPN to use nostr, the vpn just add privacy if you need to
Discussion
Sure you don't NEED to but it seems to be unanimously recommended?
It's more recommended to use a VPN on other social media because they are full of trackers and cookies who are using your ip address and location for targeting ads and more, we don't have all that on nostr and i hope we never have it, so you don't really need it here except if you want absolute privacy