[_heimdall]

These are definitely helpful, but what you are describing are all language tool features rather than features of JSX itself. 5 would be the exception, but that is just user preference of what kind of syntax one likes to write components with.

[lolinder]

Well, yes. But OP was asking about what makes this better than `innerHTML`, and the obvious answer is that support for HTML programming embedded in JavaScript strings is generally bad while support for JSX is very good across all editors.