You can’t subscribe to Netflix inside the app.
https://help.netflix.com/en/node/25097/
They’re a so called “reader” app which can send you to an external site to subscribe.
https://developer.apple.com/support/reader-apps/
Other streaming services fall into the same category.
If I recall, and from what I’m now able to find, Netflix didn’t lower their prices when they did that move. And remember they have added ads, are cracking down on password sharing, and prices keep increasing.
So while Apple’s cut is high, let’s not fall into the trap of believing that other big companies are somehow fairer and would totally pass the savings onto us. The overwhelming majority, if suddenly exempt from paying Apple’s cut, would keep charging the same thing and pocket the extra revenue.