I’d say both yes and no - Apple’s now booming services division (which includes the App Store) only started to produce meaningful revenue and profit after introducing a range of ancillary and subscription services.
Absolutely agree that any change to their business model will be a hit on their revenue - but I believe people may be grossly over stating how much of Apple’s services division profit is coming from that 15/30% share. Running the app store is easily their most costly service and stable users aren’t in the habit of buying apps - but those people sure are paying their monthlies on iCloud/storage and music. (Also not to forget that apple get a cut from every Apple Pay transaction.)
