Had Lews Therin balefired himself his soul would have been ripped from the Pattern and Rand could not have been born, if I understand the lore correctly. On a non-canon point, it would an interesting idea, death by self balefire. As this would remove you from the pattern in the past... Meaning you would not have balefired yourself. Would this create a temporal paradox like killing your own grandparents in the past? Or in the case cited, would LTT and his soul be removed from the Pattern and Ilyena and the others be restored to life? Could he have undone the attack on Shayol Ghul? I guess undoing something like that would destroy the Pattern quicker than destroying whole cities as the Age Lace is woven around such important events. To be fair, I think Jordan kept his magic system soft to avoid such paradoxes. I feel Sanderson would be the kind of author to explore the implications this would cause in a hard magic system, like he did with Gateways in his books.

Welcome to Dragonmount, Samarah. Hope you enjoy your time here, and I look forward to seeing you about on the forum.

Or it could be something inbetween that the wilders are a different lineage and that it is random. In the Two Rivers, "the old blood ran strong" and there were many wilders (or women dying as they could not control the Power) and many that be taught. So wilders could just be end of the bell curve. So depending on if the sul'dam reproduce the situation maybe similarish. (you would assume they must, otherwise they would have bred the lineage out nearly immediately, only male non-wilders would pass their lineage on). The Seanchan collar all their wilders. No offspring. In the Westlands, most wilders die (75%) and a portion go to the White Tower (no offspring). Most channelers continue reproduce in both cases. So if there are more channelers in the Westlands, this may have more to do with the old blood running strong (a more pleasant way of saying inbred? Or just a different gene pool perhaps) than any systemic difference.