I don't think not having enough versions of IE was ever a problem. The problem starts when everyone builds their app to a platform that is very dominant and controlled by people who's interest are not always aligned with the user's interests.

You don't have to compile Chromium to have a browser incompatible with the websites that people build for Chrome, you can just use Firefox or Safari or write your own browser if you want to have a web browser that won't be able to run Microsoft Teams.