Not really. Browsers just need to default stop autoplaying videos out of the screen view. Or better yet what they did to popup blockers. Give one chance to behave well, if the site doesn't then it gets blocked and the user has a notification that autoplay was disabled.
Blocking scripted calls to "element.play()" really sucks for Web developers building games and other kinds of apps. Safari on iOS did this and it was horrible for developers.
Firefox and Chrome let you mute tabs. Firefox Nightly also blocks playback in any tab you haven't actually looked at yet. Other than that there's not much they can do.
