Most people aren't using wifi near running microwaves, so it's hard to notice. Some microwaves leak more than others, but none of them are required by the fcc not to interfere with 2.4ghz wifi. The FCC says that they can actually leak an unlimited amount of radiation at that frequency [1], although obviously if it's high enough to start cooking people standing nearby other agencies than that the will get involved.

I bet ya an upvote that yours still leaks enough. One thing to try is to put your phone next to the microwave and place your bluetooth headphones or speaker riight at the limit of its range. Turn on the microwave and see what happens!

[1] https://www.ecfr.gov/cgi-bin/text-idx?SID=c7be03a4f7b02514ce...