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Unity backtracks, no runtime fee for sub $1mil or for games on current/old versions
(blog.unity.com)
This is a most excellent place for technology news and articles.
This is just how this stuff works. Unity already operates with some self-reporting reliance (although afaik they don't even require a report on the personal license), since the different tiers have a maximum revenue cap before you must upgrade. Software audits are a thing, and trying to skirt them by lying on your numbers is an easy way to get fined or sued.