This was my thought too (about the API part). From my experience, the TV app on Apple devices has a pretty good search and it shows you all the services a show or movie is available on- even the ones you aren’t subscribed to. For example, if I search ‘Modern Family’, it tells me I can buy seasons 1-11 on iTunes, watch seasons 1-11 on Hulu, watch seasons 1-11 on Peacock, watch season 1 on the ABC app, season 7 on the NBC app, and for some reason also watch specifically season 7 on 6 other apps (Bravo, Syfy, USA, among others).
I really doubt Apple has a public endpoint for these searches and data but I also have never really looked. The point is they’ve done the scraping; they have the data. If someone can leverage it and do the curation, I can see a really useful product.