Issues logging in to sourcegraph.com and this community (DNS?)

Hi, when trying to sign in to sourcegraph.com, I get “Your request was blocked by our firewall”. An email conversation with support required me to turn off my vpn provider (PIA, in this case) and install Cloudflare Warp and use that instead. However, I can access this forum using my vpn provider without issue. It seems to me that requiring your users to use bare DNS can’t be right and surely most corporate entities are using some sort of vpn. I don’t understand why any vpn should affect the services you’re providing, as an “evil” user can come from any DNS pool, right? What am I missing?