they are probably terrified of patreon banning them for it, they have a lot of patrons and a lot to lose, but is that's the case they are being really overzealous. Or they really love their assets very much
Patreon wouldn't ban an account with 2000 patrons overnight, unless they banned porn altogether, not even mr dots that was caught breaking the rules had the account deleted, he just had to completely remove DmD from the page, but he still develops it and patreon likely knows it
Irphaeus had a similar problem with Waifu Academy because of extreme content, including incest, he just never mentions the game in his page, has another game as a front for WA that he never released (but apparently he will in the near future), releases news about WA refering to it as Waifu news. Don't know how he distributes it though, probably through email