I sympathize with his feeling, but it's dumb.
I mean, it's just a downer if you're not interested in Arena because even though it's not the Persona Team (Although like I say, Soejima will have spent - what, a few weeks at least? - working on it), it's a new game that isn't the one you want, but it's close enough that it still stings.
When you've been waiting for something for a long time, and someone says "HEY! HERE IT IS....N'T" then it's pretty demoralising.