I've been trying to ask this to people posting reports, and although there are many "older" accounts (like mine, circa 2017 or older), at least 2 reports are from accounts created this year:

https://news.ycombinator.com/item?id=29710262

https://news.ycombinator.com/item?id=29711950

That would make "more sense" that our credentials weren't stored and unused for years, i.e. that this is possibly a new, recent breach.