So are Signal’s serverside components.

WhatsApp is e2e encrypted. It uses the same tech as Signal.

Ah ok. Well, as I said I lived there for years and i’m telling you they can and do block VPN traffic (not all, another commenter mentioned Astrill) quite well. To say zero success is incorrect.

Location (and peering) might be a factor, so if you/your friends lived somewhere different to I your experience may differ.

I spent years living in China. Do you really mean zero success?

OpenVPN stopped working in 2017. Deep packet inspection prevents the initial handshake. I hosted my own SS for a number of years before switching to wireguard, with more success… however, they IP ban a majority of VPS IP ranges, so the providers Linode/DigitalOcean were messed up.

And everyone experiences VPN slow down during CPC conferences.

It can only be worse now.

Used it as my primary hiking tool recently (i know, I know - I had a compass and a map) and it worked a treat.