Has Trump changed?

Steve form Brisbane had a typically thoughtful article on Trump and his decline in his cognitive abilities.
This got me thinking. I remember Trump and he has always been a braggart BUT it is only in recent times he has become an ignorant braggart.
His tweets show him up as a complete idiot. Comedians have lots to play with.

BUT am I right and is this is a recent development?

He was embarrassing in both the primaries and the election in just how much he did not know compared with the typical candidate. His 'knowledge' of ISIS and how to combat them is a prime example. His EO on Refugees another one.

We must remember he is an old man. He is an overweight person.He was clearly feeling the cold when few others were in January and February.( How could I forget the 4 hours sleep. He loves to work you see.)
He is legendary for having the attention span of a cockerspaniel in the Chaos house.
People are deliberately leaking in the Chaos house because either they show Trump utter contempt as he clearly disregards specialist advice ( think security and intelligence matters as a prime example) or because they need to ventilate views he as disregarded.

Have we ignored how old Trump is and what this involves? If he wasn't President people would simply say he is a typical grumpy old man and what that all entails.