They're sort of similar, and you can probably get the same work done in either system, but I think real threading (green or otherwise), may leave you with less cognitive load. Spawning a thread may be complex, and thinking about how the threads are scheduled is often complex, but what each thread does can be very simple -- and you don't have to think about 'long running things need to be futured/awaited', you just do things in a straightforward way in the thread (caveat: slightly less straightforward if you need thread actions to be cancellable).

Green threads may be running an event loop underneath, but it's a useful abstraction in many contexts.