^ If you trust IGN’s translation of a Famitsu article.
Regardless, Mikami quite infamously said he’d “cut off his head” if RE4 went anywhere but GameCube. Whether that was meant literally or was mistranslated to mean “leaving the company,” the meaning is still the same.
And it does hurt the bottom line for Nintendo if they’re trying to boost sales for their flagging console and after Capcom comes out and says that they’re working on five games exclusive to the GameCube backpedals shortly after and says all but one, Resident Evil 4, could potentially end up on other consoles. (https://m.ign.com/articles/2003/01/16/cgd-03-capcom-five-not-gcn-exclusive) Only to then say, two months before release that it would be coming to PS2 as well. Difference is Dragon Quest XI never promised console exclusivity.
Killer7, along with RE4, Viewtiful Joe, and two other games, were all initially announced as GameCube exclusives and were meant to boost sales for the console.
Edited for clarity.