The reason people criticize E core is because they see the trick for what it is. Heterogeneous computing is great but the PC space is not yet set up for it. You can take advantage of the E cores for lower priority tasks (like spotify running on E cores while you game on P cores) but you could also just as easily run everything on P cores and avoid any scheduller errors.
In the future this kind of architecture can be great - like imagine having the main game rendering on P cores and the static UI elements using E cores - but that's not today. Today it's only the way Intel found to be able to match the core count AMD was offering since MCM and EMIB aren't ready for prime time yet.
We can mock EMIB glue just as we mock Ryzen infinity latency until the tech proves it self, just like E cores. When things stop being just marketing ploys there will be all the reasons to be happy, until then E cores are a marketing trick, they aren't necessarily useless or crap but they aren't any marvel of engineering either.
