As Amazon becomes the latest platform to push an ad-supported tier, TV writers greet this retro model with frustration and, in some cases, disdain: “I thought 'Nine Perfect Strangers' with commercials was horrible,” says David E. Kelley of his Hulu show with breaks.
Content providers can probably include chapter markers in their content. I also suspect it’s not hard to detect a scene transition. Failing these, randomly placed.
This was my problem with hulu back in the day. Short episodes like Futurama would have a commercial shoved in at like 3 minutes and then again at 10 or whatever, it was obnoxious and shittily implemented.