Most psychologists don’t care about Freud’s work outside of a historical sense and kinda hate him as a person. His work was quite literally used as an example of pseudoscience by Karl Popper.
And yet for some reason philosophers have an obsession with integrating his views into their work and artists keep using his views as inspiration and analyze existing works via the lens of psychoanalysis.
Why?
Laziness and expediency.
Freud’s theories are pretty simple to understand and easy to map onto. Back when Freud was influential, people were easily able to import and use it in their literary theory, philosophy etc. Same thing happened with Lacan but since Lacan builds on Freud it’s essentially the same thing.
In order to use an updated understanding of psychology or even better, neurology, people would have to learn a whe lot of much more complex theory and facts, and explain it to their readers, and apply it into their own thing.
It’s much easier for an overworked academic to take this wrong but much-used system that everyone already knows.