I see that when this landed it appears that it was removed from landing on "Python 2.7, Python 3.6, Python 3.7".

Is there any chance to revisit this decision? I dug into the mimetype code and it doesn't appear that there is a way to rely on operating system mimetypes for systems aside from Windows... as such this is going to be a fairly large experience gap for people developing front-end applications that utilize the file extension on any version other than 3.8, which will likely take quite a while to be distributed as a default in various OS distributions.