My source is TFA, as I stated. This is what I see in the table when I follow the link.

For example, in the column for my current iOS version offline support is crossed out, and for the upcoming version it has a check mark.

If the claim being made is that pwa.gripe is a bad source, I can only assure I have nothing to do with the site. If they misinform visitors about Safari’s capabilities with regard to PWAs, you should post it as a top-level comment.