I doubt it pertains to Powershell "in general".
There are two "Powershell" branches. One is "Windows" PowerShell and it runs only on the Windows O/S platforms. The other is the "Cross-Platform" Powershell (begining with version 6) that runs on Windows, Linux, and (I think) Macs.
Version 7.1 and earlier (of the cross-platform variety) is no longer in the LTS (Long Term Support) category and that's what the link seems to be about. Version 7.2 is now the "LTS" version. That doesn't mean it's going away, it just means it will no longer receive any further improvements or development.