When people talk about "therapy" here, they most likely are thinking of bog-standard talk therapy, where you just go in and kinda, well, talk to someone about your life, problems, etc.
For some people, it's enough to just get things off their chest, talk about things out loud with someone and helps them deal with their issues. I personally see such a therapist monthly and find it beneficial to my mental health.
For others, especially those with more intense troubles and traumas, it may not be, and would probably be served better by someone more specialized with said traumas.
Like any medical profession, the quality of individual therapists and mental health experts can vary widely, from chuds to libs to comrades and everything in-between. there's a solid chance you may not get the perfect fit on try 1, I didn't.
I just feel like some people are dipping their toes into Scientology-ish "all therapy is bad, never seek professional help for your problems" stuff, which I think is disastrous advice.
I've been in therapy for a few months now and I can say it's actually been extremely helpful. I thought I'd figured a lot of things out myself but it wasn't until I started therapy that I realized there were more deeper issues that I hadn't quite realized.
I'm not going to write a wall of text explaining everything, but at the very least if we understand that capitalism is the root of many of our problems, including our ability to get proper help, there doesn't need to be an outright rejection of the science of how the brain works.