Here's the OED definition of racism:
1 Prejudice, discrimination, or antagonism directed against someone of a different race based on the belief that one's own race is superior.
1.1 The belief that all members of each race possess characteristics, abilities, or qualities specific to that race, especially so as to distinguish it as inferior or superior to another race or races.
https://www.lexico.com/en/definition/racism
Trump's comments are often dumb and crass, no doubt about that. But are they racist?
The problem is, to some people, virtually everything is racist these days. Some people think the film Gremlins (1984) is racist. They see the little green monsters as a metaphor for the African-American community. And because these little green monsters were trashing a pub, getting wasted, dancing like maniacs, shooting each other and generally being violent, well, that's supposed to be a dig at the black community. XD