used a proprietary license

Does the license actually mention it mines? I am reminded of a lot of "freemium"/"ad-supported"/etc. software that makes its author money via ads or whatever else --- and you agree to that if you read the license --- and it is a bit shady to name the miner 'systemd', but it seems rather overboard to call this "malware"... when I see that term I think of software that self-propagates and exfiltrates personal data, delete/encrypts files for ransom, etc.

Also from the page:

Size 138.8 MB

I'm not really familiar with the latest trends in (bloatware?) development, but a simple game like that taking >100MB would make me suspicious --- even 10MB is in the "questionable" range, and ~1MB would be closer to what I consider "typical". 138MB is bigger than the installed size of Firefox, and that's a far more complex application...