Please don't lie :/
Please don't lie :/
As for achievements, I wouldn't say it's had support for "a long time"; they were added in August 2024 (v2.15.1).
If you think that's a "lie", consult a dictionary.
As for whether my general point stands, I think it's a reasonable inference that if GOG Galaxy supported Linux, it would support Linux games and cloud saves for those games, and only then would Heroic and the like be able to implement such a feature. I could be wrong, as it depends on details I don't know, and I'm just making an educated guess.
Given I'm using Heroic from AUR on a supported OS, and installed with default settings, I consider this cloud save support to be less than stellar, but that's a separate matter, I'm not trying to turn this thread into a support issue.