MAGA supporters have become so wrapped up in “incoherent QAnon babble” that they are incapable of noticing former President Donald Trump’s rapidly deteriorating mental state — at least, that’s what Salon writer Amanda Marcotte suspects. This comes as the former president, now in his late seventies and almost as old as President Joe Biden himself, comes under scrutiny for his recent slip-ups, including confusing Nikki Haley with Nancy Pelosi and appearing to confuse his own wife with GOP lobbyist Mercedes Schlapp — both of which Trump has angrily tried to claim were intentional. You need only w…