This particular dataset appears to have been collected by malware. So it wasn't a breached company, it was malware on some machine that impacted users used that logged usernames/passwords.

That's also useful as it might lead to clues to identifying a potentially compromised machine

I think the same malware that had breached my data awhile ago "Polish Credentials" is apart of this because the same old user:pass pairs so maybe its a bunch of data from multiple breaches if you were in the polish breach it dumped your google saved passwords so that would be whats affected