Changing the code of SVG content? I don't think we should be doing that. One thing that I think would be useful for us to do is to ensure that SVGs can be scaled more easily, which was discussed here. Updates to Illustrator and Sketch have resulted in better-performing SVGs so we may not need to take that road.
Regarding this post, the core of the issue is this:
MIME type is set by the server -- so this is something you need to fix on your server.