Well, here is the rub. If we are talking about the fucktastic cuck-tards over at Patreon, then it most definitely is. If we are considering the genetic ramifications of incestuous offspring, then it is only an issue if she is the sister of your mother or father. If she is the wife of your mother or father's brother then there is no genetic danger in the relation. Now, her daughter (your cousin) will share genetic similarities with you, but at less risk. This is probably why second-cousins is ok, legally at least historically. But it has been a long time since the actual issue of why incest can be a problem is even considered when discussing the censorship or laws around incest as it relates to fictional arrangement of pixels on a monitor.