I don't think we should label dolphins as un-intelligent just because their physical environment doesn't allow them to smelt metal.
My point is - I'd like to avoid judging something as (not) alive or intelligent just because it is (or isn't) similar to our daily life.
I think this is fair, but I also think when people say "detect intelligent alien life" it is shorthand for "intelligent and technologically capable life that would also be able to develop things like radio and interstellar travel." The latter is pretty cumbersome. I don't think dolphins are unintelligent, I don't think an ant is either. But in this context that's not what we're talking about. Language has limits and we use shortcuts like this all the time. Let's just be clear what page we're on and let's try not to inject another page just because the same word is used to mean multiple things.
The premise is wrong. The premise here is that intelligence is the only factor. Physics doesn't allow dolphins to enter the bronze age. Hell, even if dolphins grew arms and hands they couldn't enter the bronze age. They're probably smart enough to do so, but there are other factors limiting them.
We have looked at Earth. We can look to the stars at the same time. It isn't an "or" operation.