Your concerns are definitely valid, but note that every time the Chrome team chooses a browser default, or doesn't include a permission setting for every possib

Your concerns are definitely valid, but note that every time the Chrome team chooses a browser default, or doesn't include a permission setting for every possible ability, they are guessing what the user wants. And these guesses will not be the same made by other browsers, so the user may still be confused why something works for their friends but not them. "Smart permissions" seem strictly better to me than allowing autoplay ads or no autoplay youtube, and reducing user frustration may just require ad-hoc tricks, e.g., filling the bank spot of a non-auto-played video with a permission dialog box. Likewise, using global trustworthiness information about a website could greatly improve guesses.