He hasn't had the opportunity to, he hasn't been first choice at Juve or Real. However, last season proves what he can do leading the line, he was key in Real winning La Liga by being their second top goal scorer.
Morata is 100% a proper #9.
@Kaner: I was referring to the fact Lukaku has been a consistent starter and has a very good scoring record only second to Aguero in the last 4 years. Morata doesn't boast the same, however, there's a reason for it.