Once Chrome does, for many devs, you can simply enforce a version check and say "please use latest Chrome" and be done with it.
Checking against version numbers helps cement existing browser monopolies, makes it difficult for new browsers to view websites (even if the browser correctly implements every feature), and encourages everyone to spoof version numbers / browser names which leads to them becoming a less and less useful signal. See any browser’s User-Agent string for an example of this