It's insanely hard (nigh impossible?) to debug an aging app that has use useEffect's and useState's everywhere. (This wasn't the case with the class components (not suggesting that class components were the be and end all))

Now the Compiler sounds nice, and sure there is going to be a lot less code. But, at what cost, it does sound like it's just more magic, moved further and further into the React internals. Which I think unfortunately gives the developer less understanding and power.

I'm just ranting, it's not like the React lib itself is yet entirely divorced from it's principles circa half a decade ago, but I fear it may. Perhaps, they could promote and support more sub packages of React itself e.g. rendering, state