Is Nintendo actively courting these games, or are publishers just saying they presumed Nintendo wouldn't be interested? Basically, did anything change and is this really a story at all? The thread title seems inconsistent with what the publishers said in the articles, which is basically that Nintendo welcomed their support, which seems like business as usual.
Wii had the likes of Manhunt 2, No More Heroes, and Scarface on it, and 3DS was the initial home of Senran Kagura, with DS itself also having similar games (GTA is the biggest one, but there were lots of 'sexy' games in Japan from what I remember). So it's not like Nintendo didn't not want 'Mature' content in the first place?
(Also don't forget that Nintendo published Devil's Third and Bayonetta 2 - that seems more proactive to me)
Maybe Nintendo wants publishers to consider Switch as the platform for these games again, while they were on Wii, DS, and 3DS, Nintendo doesn't want a situation like with Xbox One where publishers just assume Switch owners wouldn't be interested in certain games (for Xbox One it's mostly Japanese publishers ignoring it in favour of Steam.
Having Doom and L.A. Noire (and potentially GTA V) be on the Switch is a very good move if Nintendo requested these titles, since it's clear the first year of software for a platform defines how people perceive it.