Maybe there are reasons to do it nostr-natively (the IP obfuscation is not one). I agree we should use existing solutions, tor is just too slow for people to bother with usually, so it's probably more a question of making this stuff accessible with a good UX. I think a harder problem than IP obfuscation is filter analysis anyway. If your client sends 100 filters in a minute, there's a lot the relay can learn about your pubkey.