Middleboxes tend to not play well with non-HTTP content these days. Not long ago this was also the case for non-UDP/TCP protocols, this is even more cemented.

Middleboxes tend to not play well with non-HTTP content these days. Not long ago this was also the case for non-UDP/TCP protocols, this is even more cemented. The only times I know that non-HTTP works is video games and that is sorta hit-or-miss on one ISP I frequent, they block protocols they don't know for "security". Making it HTTPS is an easy way to get around any potential firewall problems and have it work easily in corporate settings.