The new Young Sheldon season 5 trailer explains why Sheldon (Jim Parsons) despises engineers like Howard (Simon Helberg). In The Big Bang Theory, Sheldon is recognized as being the textbook definition of a genius. Fully aware of this, he never misses an opportunity to assert his intellectual superiority over others, even his buddies, despite their own achievements. Sheldon, in particular, often mocks Howard since he is an engineer without a PhD. All of Sheldon's male pals in The Big Bang Theory have doctorates and specialize in the study of physics, making it simple for Sheldon to single out Howard.

Despite the fact that he was the only member of the Pasadena gang to be taken to space after developing the Wolowitz Zero-Gravity Waste Disposal System, which was installed on the International Space Station, he received no credit. 

Sheldon enrolls in a new engineering class, while he is frequently ecstatic about his schoolwork, the video shows him growing progressively irritated because he can't figure it out. This is the first time the character in Young Sheldon has genuinely struggled with academics. He eventually develops a life-long loathing of engineering, which he takes out on his pal in The Big Bang Theory.