I think that there's something up with that page. There may be a pathological path when suitable GPU support is not available.
My machine slowed down tremendously, with a YouTube video in another tab pausing entirely until I managed to close the tab. I tried again with Task Manager open and saw a process named "System Interrupts" with 75% of the CPU before I choked off the tab again.
I agree there's something wonky with the page. My argument is different: A web page should not be able to take down the computer, no matter what. Web pages are untrusted; this is a DoS threat.
Really, it also shouldn't be able to choke the browser.