ancienregimele, I think you are exaggerating a little. People most likely come to incest fantasies at a more mature age, when ordinary sex no longer evokes such vivid emotions as before, and they want new, stronger stimuli. If the topic of incest attracts from childhood, then this is already a congenital pathology.
There's no way to verify that in relation to the AWAM fanbase, it's just my opinion arrived at after 5+ years of this & until a year ago still actively playing. It's a fact, however, that fetish preferences aside, L&P is catering for kids & it's becoming clear that, apart from yet another incestuous relationship expected with her sister, (again of no interest to non-incest followers), there's no prospect of genuine adult extra-marital relationships with Sophia in sight for years to come, if they ever occur. It's years since Sophia had a truly erotic encounter with another adult. [I don't count the salon fumbling because I didn't find Clare's efforts erotic].
Such M/S incest as there is in AWAM is playing out, IMO, in a very unrealistic way but is in line with the average 3D teen porn that comprises 90% or more of games. They're relentless & the lack of variety is striking. I'm led, after the disappointment of AWAM's direction, to the inexorable conclusion, that 90% or more of game players are very young, with many having an understandably imperfect appreciation of how sexual relationships, including incest, happen & how they progress, or don't, as the case may be.
It may be "where the market is" but what happened to AWAM's unique market niche? It's looking very likely that there's never going to be a 'realistic' gaming story, written by an adult for adults.