Earlier quoted context omitted.
Tell you what. Since I'm not a big fan of the lynchmob, here's the only positive critique I'll give you: proxying isn't an altogether terrible idea. It's not my first go to, but it does have it's place. HOWEVER. Allowing a third party to manage it, is. If you genuinely want to create some buzz and interest, source the serverside of this, and write some docs up how to deploy it to AWS, Heroku, etc. Bundle the JS with…
OK, it is a trust issue. However you can use this library and change the proxy url to your own server and still get the benefit of the fact that you don't need to rewrite external requests and just use jQuery.
At that point, if I wrote my own proxy server, I'd drop the JS altogether and just request a proxy link. I know what's cross-origin in my code, so if I wanted to mitigate it with a proxy, I don't need the additional library. Still say your best bet is losing the JS and opening up the server. I mean, what's going to be better here, telling everyone "it's a trust issue", or passing on a relatively simple self-hosted proxy server made specifically for CORS-faking? Else, my big trust question is "why exactly do you WANT me to forward my traffic through your black box server?"