Where is the video link? I couldn't find it in the article.

Russia, China & UAE are quite successful with blocking VPN's. I wouldn't be so sure that in near future UK or any EU country censorship or heavy restrict VPN's.

It seems so.

Is there any page where Jerboa devs describes what is the policy for backward compatibility?

Since not all servers updated synchronously with new Lemmy release it's a good practice to support several older versions.