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You might be surprised: https://playcanvas.com/explore
Ah, my old Intel HD 2000 is on Chrome's hardware render blacklist (for good reason, disabling it is hilarious). WebGL is amazing though, I agree; http://acko.net/ is how all websites should work. :D There are also well-polished JS games like http://zty.pe/ (that don't require WebGL); that game in particular is built on a nonfree JS game engine, but it's a good demo of what's possible with efficient coding.
I've got some similar things I work on for fun but what you've posted is pretty remarkable!