the difference is that in the "no autoplay ever" case I would be not able to enable it if I wanted. "No autoplay by default" is the reasonable initial setting, while still giving users a choice.
There is no good reason to have Audio off by default and have no way to turn it on for games.
http://www.phoboslab.org/log/2011/03/the-state-of-html5-audi... (Year old, but still valid)
Apple have been fairly supportive of WebGL: it's been in the WebKit nightly builds for almost three years now, of which Apple are a major contributor. You can accuse Apple of many things, but given how they've been part of the WebGL Working Group from its formation I'm not so sure you can say they're out to 'get' WebGL...
But developers care, a lot. You have no idea how many popular games use Ogg internally.
Here's a small list: http://wiki.xiph.org/index.php/Games_that_use_Vorbis
Looking at the games, I wouldn't be surprised if a billion copies have been sold to date.
Audio cannot be streamed playlist-style, one after the other - again, it always requires user input.
So this screws things up completely for html5-based games with audio.
Hell, it's not like Android is a shining example of audio support: http://code.google.com/p/android/issues/detail?id=9372
And don't think I'm not affected as a developer – all the time people use our product, Hype, to create content that includes audio and video elements, and we're stuck explaining to them the behavioral differences between desktop and mobile browsers.
Apple's not evil; they're pragmatic. Right now, users needs win in this situation. Hopefully we get a more flexible solution in iOS 6.