Apple just doesn’t work that way, and hasn’t since I worked there in the 90s. Private APIs are out of bounds. It’s like a “the FBI doesn’t negotiate with kidnappers” situation.
Apple's private API situation was also much more nuanced, back in the days if Adobe was using an API, private or not, it probably wouldn't be degraded in any way until the core applications moved forward. Current Apple might not give a damn though.
Yeah true, there was a period when they couldn’t really afford to annoy the big developers. But it doesn’t seem like the underlying attitude changed much!