I actually think that's unfair on Trump.
Musk has utilised some of his wealth to develop a company that is competitive in the space business. I can accept Trump thinking that is "good with rockets"
Kennedy was instrumental in getting the US to the Moon, but he had zero rocketry knowledge as far as I am aware.
However his comment about the wheel, to me looks like he started listing US inventions and then his mind drifted and finished listing inventions.
That's not normal, but could be expected if Trump is mentally declining.