I'm no fan of the auto-everything web, but I don't think your analogy here is sound.
Since we're ripping this analogy to shreds anyway, let's take a different view: You call up Starbucks on the phone (i.e. visit their website) and request that they read you their new menu and describe to you their new store location (read: you click on the link with the info you wanted). Before they do as you asked, without warning they turn on a megaphone, point it to the receiver, and start playing a looping advertisement for a new Harry Potter line of toys. You didn't ask for that Potter nonsense, you're now deaf in that ear, everyone around you is looking at you funny, and you hang up the phone in disgust rather than wait through three iterations of toy pimping just to find out some simple information they claimed to have on their info line (website). Then, on your next phone bill you see a per-minute charge for that call (as in, they used your metered data to spam you).
Just a thought.
That's what autoplaying ads and videos on the web do: They catch you off guard with loud, annoying audio that you can't always just turn off, and if you're on mobile you're paying for the privilege with your data allowance. You didn't ask for it, it attacked you without warning.
> A call for browser vendors to implement some opt-in setting that does what you want would be much more realistic suggestion.
On this I agree with you entirely, and I think that's what the OP is actually asking for.