Oda is asked a question.
He replies good question.
The question is why did Goofy get a weak devil fruit. Oda clearly agrees with the premise hence him saying good question. So we are led to believe that Goofy's devil fruit is weak.
In another translation this is even more apparent by Oda saying hahha true when you consider all the other
strong and cool abilities.
It's perfectly clear that Oda agrees with Luffy's devil fruit being weak.
A mythical zoan devil fruit is by no means weak. Those are even far rarer than the logia class.