In fairness though, following your (correct) logic that strikers can improve, there is nothing to say that McNulty wouldn't have improved on his previous returns in L1, particularly off the back of a great season last year.
It is just political pressure, not with a specific aim. I think it's a good statement and respect him for doing it. It's non partisan and just states facts.
Considering the number of players we've used in the last 17 years, a debut is a pretty regular occurrence, not like it was years ago. We've probably had over 11 players making a debut at some point in every season for a while, be it new signings, youth players or loanees.