> Yeah, though AFIAK these event loops still suffer from blocking on (eg) complex json parsing or anything CPU driven (where real multithreading shines).

This is only a problem if the JSON parsing is being done inside the event loop itself. The idea here is that you'd have a separate JSON-parser service that the code in the event loop passes the JSON into, then continues executing the other operations in the loop while it awaits the response from the JSON parser.

Just translate anything you'd spawn a parallel thread for into something you'd pass to a separate endpoint -- that's what I was referring to when I said that the poor multithreading can be easily worked around if you're achieving parallelization by orchestration of microservices.