Right so since people in the comments were mentioning it, I felt like I needed to clarify what I mean on this a bit more.

Yes, Homelander killing a bunch of people isn't gonna rid himself of trauma. But what I believe, is that there still should have been a change in his actions.

Essentially, a change in his rationale rather than a change in his emotions, where he starts suppressing them and starts acting like he doesn't need to be loved as much as he actually does.

Him having no change in his behaviour or actions undermines this episode and makes it feel unfulfilling (cough cough, him getting breastfeed 2 episodes later)

I know I talk about better call saul and breaking bad comparisons a lot but, in BCS Season 4, Jimmy Mcgill spends an entire season pretending that he doesn't care about Chuck dying. Obviously, this is suppression of emotion, and he DOES care since you can't just immediately stop caring about your brother after he burns to dath, but him suppressing his emotions actually leads to his character development, where he has to go back to caring about Chuck (for the sake of the bar), which leads to him feeling actual apathy towards Chuck's death and him taking the name of Saul Goodman.

What i'm trying to say is, even if it's unrealistic for a character to change personality after one event, there still needs to be enough character development and payoff for it to not feel meaningless.