Sourcegraph CEO here. We 100% agree, and that's why we built Sourcegraph. Check out our roadmap at https://sourcegraph.com/plan.

And try browsing code on Sourcegraph: https://sourcegraph.com/github.com/gorilla/websocket/-/blob/... (we support other languages as well). Right-click on "parseURL" and choose "Find All References". If you click on "HasPrefix" a few lines below, you'll see a cross-repo jump (and the right-click menu lets you see global/cross-repo references).

Sign up at https://sourcegraph.com to get it on your own GitHub repos.