Sounds like you're just criticizing try-catch style error handling, rather than criticizing algebraic effects specifically.
Which, I mean, is perfectly fair to not like this sort of error handling (lack of callsite indication that an exception can be raised). But it's not really a step backward from a vast majority of programming languages. And there are some definite upsides to it as well.
I’m not a fan of how ‘await’ works in JavaScript because accidentally leaving it out causes subtle bugs. But the basic idea that some function calls are simple and return immediately and others are not makes sense.
I agree that await is a nice hint in the code that something more substantial is happening, but ultimately it’s limited and quite opaque.
Great IDE support for algebraic effects would probably include inline hints to show effects.
Maybe some effects should have call sites annotated, like ‘async’, and others should not, like DOM manipulation? It seems like an API design issue. What do you want to call out for extra attention?