That is true.
But consider how else Nintendo is going to advertise the next wave of DLC. If the character is released the same day (doubtful) he would need to end with something that keeps fans on their seat as well as expectations on the next set.
This is a really good point. To anyone doubting that we'll get at least a double reveal, consider this:
A) 35 minutes dedicated solely to one character reveal/gameplay showcase when it only takes 1-3 minutes for a second reveal at the end of a Smash specific direct? Yeah, I think not.
B) You honestly think that they won't give at least an announcement of Fighter Pass 2 sometime during the direct? C'mon, it's guaranteed. And what better way to hype people into buying the next mystery box than to reveal the first pack of the new set?
C) Given the current development cycle as we know it, fighter #6 has to be almost done by now. If Terry can get revealed with nothing but a splash screen, I don't see any logical reason to hold back on 6.
I predict that 5 will be released same-day on Thursday while 6 will take at least 2-4 weeks so as to make time for the devs to potentially balance out 5.