No they're not. They're fish.......Oh wait.
They may indeed be highly intelligent. That's easy to accept. But are they as intelligent as us? Probably not. More intelligent than Chimpanzees, possibly. But people they're not.
In as sense they might be comparable in intelligence to people who are, shall we say 'mentally challenged'. Many people like the function well enough in society because the basics are there. They
can recognise themselves in mirrors and even learn a simple symbol-based language. The also have distinct personalities and can cooperate and learn from each other.
We accept people like that because they are at the end of the day our own species. But Dolphins are not. Beside if they were really that intelligent. They wouldn't get killed as often by fishing nets. We humans would have put the word out long ago. Avoid the nets. Dolphins apparently never learn and die in droves. Admittedly the same could be said of humans when it comes doing stupid things. But we rarely get killed having dinner, do we?