Short answer – No; and it is certainly a possible (and far too common) outcome.
Self justification is definitely one of the dangers of intelligence (just as it can be a strength), and it is not all that intelligence is.
At worst, intelligence allows one to out argue any opponent, without really doing the hard work of looking deeply at the assumption sets present (and there are always unexamined assumptions present).
At best, intelligence allows one to examine and unpack the assumptions that got one to where-ever it is one is. And if one is diligent in that process, it leads to probabilistic interpretations and evaluations of all evidence and interpretations (the simple notions of True/False are seen for the simplistic models that they are).
And reality for every intelligent individual is sufficiently complex that it will likely contain elements of both in practice (reality s eems to be sufficiently complex for that always to be true).
So if one is using intelligence effectively, one is constantly scanning for new levels of such unwarranted “self justification”, and they are never easy to see, or fun to find; so there are often levels of avoidance and “self justification” present and/or emergent.
Just part of the “joy of being” – a certain level of humility is constantly required.