Saying its an observable invokes a messy gray area in people's brains. I know this because I've had to explain observables to co-workers more times than I can count in my career (I'm a big fan of RxJS, I didn't mean what I said as a dismissal), and I like them for async work vs promises in many many cases, but the nomenclature does not invoke easy understanding
When I break it down to folks explaining its stream processing over iterables or async work and you subscribe (and can unsubscribe) a pipeline that runs over that stream, people get it quickly.
When I say you can "observe a stream" people start getting other connotations, for some reason. I have ran into this over and over and over. Smart people too, not talking about just juniors here
When does it start? How do you deal with oversubscription? Late starts? Double subscriptions?
On top of that streams are always a pain in the butt to debug.
The fifteen million obtuse methods/operators didn't help either (I see there are significantly fewer now).
And to remind you: it took the author of RxJava several months to understand the programming model: https://twitter.com/dmitriid/status/811561007504093184
`observers` do exist in RxJs by the way: https://rxjs.dev/guide/observer
Also observables are more like streams than arrays.