No.
There may be some kind of intelligent extraterrestrial life somewhere in the universe that looks like or is biologically similar to reptiles. That depends on how different life is likely to be and the bounds specifically on the forms that intelligent life can take.
But the only thing that one needs to believe in order to find that the reptilian theory is not parsimonious is that human beings can be cruel to each other and tremendously self-serving.
Does anyone really, truly believe that that is not true?