Ash Parrish, writing for The Verge:

The game developers affected by Unity’s new pricing model are striking back. A collective of developers across 19 companies, mostly based in Europe and mostly developing mobile games, has put out an open letter urging Unity to reverse course on its recently announced pricing model changes. The letter contains some of the same sentiments expressed by other developers this week but with one big twist.

“As a course of immediate action, our collective of game development companies is forced to turn off all IronSource and Unity Ads monetization across our projects until these changes are reconsidered,” the letter read.

Essentially, these companies, which represent thousands of games with billions of downloads, have blocked Unity from making any more money in their games. Some of the companies represented in the letter include Voodoo.io, Azur Games, and SayGames, with each claiming over 100 games.

There have been numerous messages from developers urging the company to reverse course. Others have threatened to never use Unity again or port their existing projects to other game engines. This collective action from developers represents the next escalation in the fight between Unity and its users.

At the heart of the matter is the news that Unity will update its pricing structure to charge developers for each installation of a Unity game after specific download and revenue thresholds are met. Though Unity asserts that only 10 percent of its users will be affected, it is still unclear how Unity intends to track installs and how it intends to differentiate a “valid” install from an “invalid” one.

Beyond monetary concerns, developers are also angry because the new pricing represents a breach of transparency Unity established with regards to its terms of service.

It is common for companies to often change their terms of service and terminate agreements based on TOS violations. In 2019, Unity did just that, terminating the license for software company Improbable citing TOS violations. The action caused outcry in the community, and in response, Unity reinstated Improbable’s license and committed to keeping users informed for future terms of service changes.

In a blog post in 2019, Unity wrote, “When you obtain a version of Unity, and don’t upgrade your project, we think you should be able to stick to that version of the TOS.”

[...]

According to an email, a Unity representative acknowledged that the company’s ad monetization programs had been paused for an app and remarked that it was likely because of the new fees. The rep went on to say that, in response, Unity would suspend its user acquisition programs for that app — essentially limiting the app’s ability to attract new users.

Though this action will hurt these companies financially, to them, it’s not just about money.

“The new regulations from Unity will affect every project that doesn’t generate sufficient income per user,” said Nikita Guk, CEO of PR firm GIMZ, who organized the letter. “Pushing developers to either migrate to alternative game engines or place even greater emphasis on monetization, at the expense of creating immersive gameplay experience.”

So far, 19 companies have signed the letter, and more are urged to follow suit.

“If you share our sentiment, we call on you to join us. Turn off Unity monetization until a fair and equitable resolution is found.”

This won't end well, and it shouldn't end well either, Unity's changes will affect the entire game industry.