The thing is, if you've not defined precisely what it means for a dolphin (or human) to be intelligent, then, yes, there is room for other handwaving besides yours, even in a world where the otherness dogma has been loudly rejected.
In the hard sciences there is no room for opinions in areas where we have the facts. E.g. electrical engineers don't have to entertain someone who has invented their own equation for how a transistor works which is completely different from Ebers-Moll and yields the wrong results. That's just a kook; move on. Things they try to build based on their wrong model will not work.
If you dislike hecklers who are not easily dismissed kooks, either stay out of soft fields, or else avoid situations where you might engage the public.
In the hard sciences there is no room for opinions in areas where we have the facts. E.g. electrical engineers don't have to entertain someone who has invented their own equation for how a transistor works which is completely different from Ebers-Moll and yields the wrong results. That's just a kook; move on. Things they try to build based on their wrong model will not work.
If you dislike hecklers who are not easily dismissed kooks, either stay out of soft fields, or else avoid situations where you might engage the public.