I think, if you have a system administrator, you're not the target audience for localtunnel. This is for home users who don't understand how to get their computer+router+apartment building's switch+etc to cooperate in getting them a public route.
Maybe they should just make it bind to a port below 1024, so it requires root/Administrator privileges to run. Then, if you are your own sysadmin, you can let yourself in--and if someone else is, you'll have to take it up with them.
The real barrier to entry is the point between "cheap" and "free"--especially when first learning. For me, that was when I was 10/11. No chance of getting hold of a credit card to get a "cheap web host or VPS." I could only experiment with what my computer was willing to do on its own.
Heroku's almost the right thing for this, I think, though it still requires a credit card to sign up fully (it doesn't technically, but it does to enable free add-ons, so without a credit card you don't get, say, database persistence.) Obviously, Heroku is geared for adult developers--or, more specifically, to start-ups that Heroku hopes will become monsters dependent on Heroku's stack.
What would be perfect is a service like Heroku, but specifically for people learning to code; maybe something joined-at-the-hip with an online coding-school website. When you attend a real CS program, you get access to the labs and mainframes to test your programs on--where's the online version of that?
So, anything like this already exist? Or should I build it?
I just think of a 10-11 year old putting their personal--or their family's--computer straight onto the public web with some random hacked-together code, and it makes me feel very nervous. What are the chances they are going to understand all the security implications? Pretty low, I think.
On the other hand, no one ever learned much by always taking the perfectly safe path. And who am I to judge whether people are "ready" for the Web? It's the old freedom vs. security argument.
Amazon does provide a free tier of EC2, which is great for tinkering around. But it takes a certain amount of knowledge to get one working as a web server. A tutorial, or a project that makes it easier, might be a good place to start.
Maybe they should just make it bind to a port below 1024, so it requires root/Administrator privileges to run. Then, if you are your own sysadmin, you can let yourself in--and if someone else is, you'll have to take it up with them.