Unity planned to jack up the charges for developers so that they covered each game installation (beyond certain thresholds). It then tried to 

Unity tried to clarify the policy, saying it will only count "net new installs" on any devices starting January 1, and devs would not be paying fees on re-installations, "fraudulent" installs via botnets and the like, trial versions, web and streaming games, and charity-related installs. Unity claimed that "90 per cent of customers will not be affected by this change."

Within 90 minutes, Unity's tweet had been viewed over 1 million times. Pushback had built over the last five days, and Unity's offices had to close after there was what was called a "credible death threat" over the charges.

The development community did not take kindly to these proposed changes and clarifications, and many teams across the globe, including Rust 2 developer Facepunch Studios, said they won't be making their games in Unity now. Others, like Massive Monster, threatened to delete its Unity-made game Cult of the Lamb on 1 January should these changes happen.

Unity was posted on Twitter/X on Sunday afternoon. "We apologise for the confusion and angst the runtime fee policy we announced on Tuesday caused. We are listening, talking to our team members, community, customers, and partners, and making policy changes. We will share an update in a couple of days. Thank you for your honest and critical feedback."