Phones historically have been weird for not cutting off part of the image that CRTs and even flat screen TVs have been known to do.
Yet TV manufacturers, for some reason I cannot wrap my mind around, continue to implement it, often by default (or in the extreme case, as you mention, with no way to disable it). And so title-safe areas continue to be an issue long after the obsolescence of the technology they were invented to work within.
And even if you don't care about watching the film in the right conditions, isn't it annoying to know there's something you're missing behind that notch? It's like having somebody's head in front of you when you go to the movies. Also, there are many films that have a 2.35 aspect ratio, which is wider than 19.5/9.
Sure most of the videos are not films and you wouldn't use a phone to watch films in the first place, but for that price I expect those little details that make the difference. I think Apple has lost that in the recent years.