This reminds me of Dropbox, but with the difference that Dropbox was for non-developers, whom does not know how to share files. Most developers already know how to use SSH, so what is the main selling point for this service !?
Everyone I've seen using something like this or Google cloud shell is doing it to get around oppressive corporate proxies to get some kind of work done.
Proxies like Forcepoint/Websense are content-aware enough that simple tricks like having sshd listen on port 443 don't work.
The big one is convenience: if you need to do some quick maintenance from a computer you're not usually using, it's fast and easy to do so here (e.g. if you want to administer your server from a firewalled work PC, or from your parents' house).
Proxies like Forcepoint/Websense are content-aware enough that simple tricks like having sshd listen on port 443 don't work.