I didn't listen to Q&A yet but judging by the reactions Malevolent went about the following way:
Harlan: I'll make an evil entity posess this guy and sprinkle some curiosity and other stuff onto it just for funsies
The audience: LOVES John
Harlan: Ok this didn't go according to plan... No idea why they love him so much but fine, he's not ending up as a villain, let's explore another route. BUT I'll make ANOTHER, properly evil John, they'll sure won't be able to stand him!
*adds A LOT of genuinly sympathetic stuff to the character*
The audience: YELLOW IS UNDER OUR PROTECTION HE'S OUR CHILD *loves Yellow probably even more fiercely*
Harlan: The f-... WHAT am I doing wrong???
(Jk I'm pretty confident at this point the guy knows exactly what he's doing 👍 But he also writes Kayne the ultimate troll and that's a thing to remember)