The phrase "stable genius" did not originate with Trump, It's a phrase which has been in limited use due to the fact not less than 1959, which happens to be the earliest use with the phrase I could find. Why do persons confuse between similar or connected words and phrases: https://reidzxrix.widblog.com/91314119/getting-my-the-genius-crow-vs-similar-puzzle-games-to-work