Charles Soule probably knew that Ben was getting redeemed in TROS, hence the Rise of Kylo Ren not featuring any child murder and retconning TLJ’s vague implication that he personally slaughtered all his former classmates. The extended canon materials always gave quite a sympathetic view of his childhood, but I doubt anything pre-Rise of Kylo Ren was written with his redemption explicitly in mind. I imagine that with the comic Lucasfilm wanted to explicitly steer away from making him seem like some kind of school shooter parallel. I mean, it’s bad enough with Anakin - I’m not sure if Vader’s redemption would have been popular if ROTJ had come out immediately after ROTS!