Honestly, in this day and age I consider VPN a basic internet hygiene. There are many many reasons to not trust your ISP and the wire between your home and ISP. You have moderation here, why do you even need to block VPN? I registered this account from VPN, but I somehow cannot comment from VPN? Doesn't make much sense. I'm using paid Proton VPN servers, and btw I've seen Proton having a dedicated community here on this platform.
I’m also using paid Proton VPN and have issues posting comments every day. If I stick to non-American servers things generally work, but if my random connection picks anywhere in the US, my comments won’t post until I switch and switch and switch and find a random server that works. I’ve rage-deleted quite a few comments after they refuse to post. It’s really pretty frustrating, but I won’t stop using my VPN to make Lemmy work better.
Turns out, a lot of other Lemmy instances allow using VPNs just fine. Here's thread with some recs: https://lemmy.world/post/19205545
In case you don't know how instances work, it's basically distributed system, we can access the same communities and post there from other instances (without VPN issues).