I think the link should be changed to the 1.15 release notes (now published): https://golang.org/doc/go1.15 -- these are much more interesting and useful.
* In any remotely trustable and reliable way; random PPAs relying on somebody's free time don't count, IMHO.
I've noticed Ubuntu, Debian, Centos, and Oracle Enterprise Linux are always trailing by quite a clip. Often years.
The strategy I've been using is to just manually install it on the machines where I need it. The production go versions only get updated as required.
Arch Linux.
I just saw the release when I was checking for updated versions of packages I maintain, and built it before users started bugging me about outdated go binaries.