Apple still has search ads: https://searchads.apple.com/

From the first of those listings: “Today, our technology and services power advertising in Search Ads in the App Store and Apple News.”

This meets one of the criteria you specified (“They also have their own ad platform […]”), but not the other (“[…] that will benefit from this”).

Apple’s search ads will indeed benefit greatly from this change. When an app developer runs an ad on Facebook, and a user converts and buys the app, attributing that conversion requires “cross app tracking” that will be banned by this update. On the other hand, if the developer runs the ad though App Store search, Apple will be happy to attribute the sale to get paid. One could reasonably guess that the real purpose of this change is to take that market from Facebook.

Search Ads don't count why?

That’s quite impressive research! Why did you decide to look for this?

I just googled "Apple Ad platform" lol