Granted infinite money as a child in an incident that probably left him with a grudge against poor/lowerclass, only father figure was his employee/servant, company full of sycophants that make his money for him leaving him to do whatever he wants, superpowered "peers" on the Justice League often behave in an obsequious manner towards him while trying to placate him out of fear. Guy just never had his ego checked on a regular basis and it's just gotten worse over the years aligning with his worsening behavior.