We hardly got to know Byrne's Wildchild, though. He was a fantastic character design, but what little we saw of him was while he was under a type of mind control. So we know he was smart, and feral, but we don't know if he was really a bad guy or just Courtney's victim like Lil. Him and Lil seemed pretty friendly at least, which makes me think he was at least sociable some of the time, and then there's that retcon later where Madison says they were best buddies before the flight program was disbanded. And you're ignoring all the character development that happened between Byrne Era and Post-M-Day. His history is convoluted, but there were some lovable parts. Now he has no depth, they treat him as filler. Just something for Wolverine to beat up again.