Here’s a better example: the use of GPL software (primarily Linux and busybox) by Linksys when they made their wrt54g router was used to compel them into releasing the source code of the firmware for that router. Subsequent GPL enforcement by the SFC made Cisco release full firmware sources for a whole series of Linksys routers. Thanks to those sources openwrt, ddwrt and several other open source router firmwares developed.

I can now run three openwrt routers in my home purely thanks to the GPL. If those projects had been MIT licensed, Linksys and Cisco could have just politely told everyone to go suck a lemon because they would have had no obligation to release anything.