I imagine you wouldnt say the following-“The pesak should be its assur to learn in kollel if you need to be supported. Even if its muttal meikar hadin(Rav Moshe says if its the only way that its ok-as i recall), “Es pas nisht””
We dont just make up issurim because you decide its pass nisht
The psaq here should be that one should avoid any negiah with a niece of nephew of the opposite gender. Even if something may be ok mikar hadin, it's still "es past nisht."