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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.
It's just much more likely that they massively overestimated what they could get away with and were surprised they couldn't. They were almost definitely scrambling here when the bad press and reactions started.
The situation and plan is shitty either way, but your case implies a level of intent and competence that I'm really skeptical about. Much more likely they figured all the app cash cows would grumble but mostly accept it after some mild pushback. Really unlikely they expected it to become front-page tech news everywhere.