I haven't dab in NTR path yet, but when Alexia cheat, her partner aren't human, right? Andras, being a demon, him having bigger equipment than humans is normal. Next is Greyhide who is a minotaur, again very credible to have a bigger member than humans. The succubus use magic I believe to make a cock, so the length isn't an issue. Every partner Alexia has have a justifiable reason to be bigger than Rowan, I would say it is simply a consequence rather than dev going out their way to make Rowan smaller than Alexia's cheating partner.I like how you claim its wildy irrelevant to the game when the game goes out of its way to make Rowan smaller just about everyone that bangs his wife. I mean it consistently happening certainly isn't a clear pattern at all or anything. As for it being a plot point, I don't think it would take a whole lot of writing for Corrupt Rowan to just decide to give himself a bigger dick for petty reasons, since thats something corruption clearly does in this setting. Then its just a thing from there on out. Hell maybe the corruption settling into Rowan just happens to make him sexually enchanced, since corruption clearly changes people in general. I'm guessing corrupt Rowan is going to start getting a bit more demonic right? It never had to be a potion, it never had to be a major plot point or plot point at all. It literaelly could have just been a side effect on whatever path "Chaos" Rowan takes. You're taking a simple example of something and blowing out of proportion, to avoid addressing anything I say.
Still, what is your point for going about this? Others cock size is only relevant when Alexia cheat, so in this case, you don't like Rowan being so smaller than beings who can easily have bigger cock. I suppose on NTR path, you want Rowan to get Alexia back, but the issue you have is Rowan can't get her back because he is less endowed, correct?