Poppycock and twaddle.
Mr. Trump - excuse me, former and future PRESIDENT Trump - is utterly immune to flattery. On an almost DAILY basis, he is complimented on his humility and aversion to vainglory. People come up to him all the time and say, "Mr. Trump, thank you for being so down to earth."
As to intellectual vulnerability, do not be led astray by the packs of fast-food ketchup in his suitcoat pockets. The man's brain is always two steps ahead in three dimensions of ancestors creating future possibilities from past achievements living here now.
As to his psychological status, no less a luminary than Sigmund Freud's godchild's nephew said that President Trump is more psychologically fit than any president in history.
TWADDLE, I say!