It's actually worse than that. The vast majority of IAP revenue comes from the bigger mobile game publishers.
Not only do Apple take 30% of this, they screwed over all those developers by removing their (ad platforms mostly) ability to track users, thus breaking the developers monetisation model.
I honestly find it hard to believe that they didn't realise that this was going to hit them hard with IAP revenue, but then I've always been surprised at the lack of joined up thinking in large companies.
Yeah, but this one actually hits their revenues. It's disguised for now because their ad platform is way up, but over the longer term this will absolutely crater their app store revenue.
Therefore, I suspect that this will be substantially weakened/rolled back over the next few years (this process has already started, btw).
Not only do Apple take 30% of this, they screwed over all those developers by removing their (ad platforms mostly) ability to track users, thus breaking the developers monetisation model.
I honestly find it hard to believe that they didn't realise that this was going to hit them hard with IAP revenue, but then I've always been surprised at the lack of joined up thinking in large companies.