I guess it's not clear to me how adding per-install fees (as opposed to revenue split) would increase the reach and depth of their ad network? Specifically I'm arguing that the boneheadedness of this decision (and its honestly shit communication) is probably not related to their 'new ad network masters', and is reflective of long-term problems that have been at Unity long before the IronSource merger.
The reality is that Unity was always bleeding cash. Ever since it's IPO, it's been cash flow negative. Like a significant amount. Their last filing before IronSource merger stuff starts showing up is 2022Q4, and it has $323 million revenue, and net loss of $250 million. Their claimed R&D expense was $248 million, cost of revenue was $112 million, and sales and marketing and G&A both about $100 million.
Even after their merger with IronSource (so looking at their 2023Q1 filing), they are $500 million revenue, net loss is $253 million. Basically looks like IronSource's business is roughly break-even.
Framing this as a company chasing "higher profits" is a bit misleading. This is about a company trying to chase "not dying" and floundering. Unity pre-merger and post-merger was not a company that could 'just keep the status quo'.
In fact, if you frame this from a game developer centric standpoint, what you've actually seen happen is a game engine developer try just about everything EXCEPT adding a per-install fee/revenue-split for decade+. Like pre-merger, Unity was already an ad company - it was pulling in half its revenue from its existing ad network. Unity did so many contortions to try to make a minimal strings attached game engine work as a business (and it has not succeeded).
Now for Unity (the ad company) to successfully make profits deploying ads through their game engine, either their ad business needs to become vastly more profitable (which it won't - ads can be profitable, but it's not magic printing machine), or their game engine business needs to not being a gaping bleeding wound. And hey, that's actually the exact priority that Unity the game engine company would have.
I am not excusing their current actions. But it's plain as day that they need to generate more revenue from their game engine business to be a viable business at all.