i wouldn't call that dementia thats just an old man not understanding technology
dementia is how biden was acting towards the middle/end of his presidency.
Trump is just a dumb old man at this point. that isn't dementia, nobody is as sharp as they were young as they were old. Even then, Trump was never a big brain.
Medically, an earlier stage dementia isn't all that unlikely given his symptoms. Taking multiple MoCA screenings and "preventative" MRIs clues you in on what they actually think.
He's had clear disinhibition issues. Cussing in interviews. Even saying "we can talk about sex" at an investment summit Q&A. A clear increased irritability with his staffers as he was reported screaming at everyone over the two downed US pilots incident in Iran. The increased aggressiveness and mood/personality shifts, of wanting to get into heaven.
Rambling speech and word salads. Getting distracted and going off topic, Rubio even having to remind him to get back on topic, and him reading the note out loud telling him to do so. Also, the prevalent Adderall or similar stimulant usage, keeping him up late at night sharing tons of posts on his truth social, even AI videos of himself, and ranting. Stimulants are often prescribed in early dementia for focus/concentration issues. Then there's of course the family history.
Sure it's not a guarantee, but it certainly seems like MCI at the minimum at the moment. Possibly even an early stage of a vascular dementia (think the rumored TIAs he'd been having), but more likely frontal variant Alzheimer's disease, imo.