Presumably they're still loading a version of the website which Trident/Edgekit which used to make up for the discrepancies between the other browsers.
The Edge devs went out of their way to craft a useragent that doesn't trigger Edge UA sniffing, which is why the pages used to work until Google intentionally broke them in Edge.
Do you have any sources that talk about these breaking issues? I wouldn't be entirely shocked that Google would be doing this, but I do want to see more than just one anecdote that it's ill intent rather than incompetence.