The situation is more complex. For instance I have a subscription to a magazine publisher that pushes me any new issues of several magazines as they are publi

The situation is more complex. For instance I have a subscription to a magazine publisher that pushes me any new issues of several magazines as they are published (roughly 10 to 20 every months). And the content of the subscription is not fixed, for a few months some magazines appeared, and other disappeared. Some of the content is gore/mature, while not straight porn. The catch of course is that the subscription payment goes to Apple, and only Apple (no concurrent web version exists), and additional in-app purchases also go through Apple, no bypassing. There is also audio subscriptions apps working on the same principles. The one I follow has been there for years. Basically, as long as Apple gets a decent cut the "browser" nature or fine grain policing content doesn't seem to matter much.