Like most stereotypes, elves always have sex with orcs/female knights and goblin caves/female heroes and demon kings. This is mainly because sexual fantasy is the primary driving force.
i think what they are saying is if you look thorough most of the Furry content its
1. Largely Visual novels (which is kinda a problem, but not to a major degree)
2. The "hero" 90% of the time is of some random, isekai, generic human who earns the instant love or attention of everyone around them.
3.They all preach the same game, almost same story/reasons to the "plot" and reward with nsfw scenes /sex.
its why i said self inserts is my head cannon, cause typically the actual writing, to plot, to reward never flows or makes any sense in a real/satisfying progressive way.