While I can kind of see what they're getting at, and I've seen something like this set of attitudes permeating the culture of a Reddit forum for (mostly US) psychotherapists that I spent a while reading a year or two back, it's not something that's I've seen actually coming through in the practice of therapists I've seen personally, as a patient.
I couldn't give you a precise number, but I guess I must have seen easily a dozen different people for therapy over the years, more if you count those leading/facilitating group therapy. Some just for a few sessions, some much longer. NHS, private, and through organisations (like college, university, or charities). Psychotherapists, counsellors, clinical psychologists, counselling psychologists, CBT therapists — lots of different titles, lots of different levels of training, lots of different memberships of and affiliations to professional bodies, and lots of different theoretical orientations.
This whole thing of framing everything as groups and binaries and power and oppression, encouraging you to think of yourself as a victim of social hierarchies and the sum of your identities, encouraging you to shift the locus of control entirely outside yourself and into a nebulous conception of "society", just hasn't ever happened within my personal experience.
Having said that, my personal experience is that of a white, middle-class girl/woman with a very obvious serious mental illness, so it's possible that firstly, there's just not much apart from my being female for them to latch on to, and secondly, it's harder to attribute the kinds of difficulties I have solely to oppression. The only thing I've experienced that's vaguely close to what's being described is therapists trying to help me think of my ASD more positively, or reframe past events using my current knowledge of the fact I have that condition.
TBH I think a lot of the conversations about things like sexuality, race, culture, class, sex etc., and how those are relevant in the therapy room, need to continue to happen, because they're relevant in people's lives and to the things they seek therapy about, and issues around these things play out in session as well as needing to be tackled in therapy more generally.
For me as a patient/client, it's fairly easy for me to find a therapist who is likely to have a good general grasp of what it's broadly like to be a white, middle-class, educated woman who lives and grew up in the UK, because most of them fit that description themselves. Nothing I say to them about my family background and family expectations will have to be explained, the ways the world reacts to my basic demographic features will not be something I have to convince them of, I will never have to double-think the things they say to me and wonder if they said them because of bad assumptions they're making about my background or cultural heritage.
I have had some questionable attitudes to my sexual orientation from mental health services more generally, and MH services are no less vulnerable to prejudice towards those with mental illness or neurodevelopmental disorders than other people are, IME, but therapists in particular, I've really not had that much difficulty with.
I prefer it if therapists are aware of ways in which life can be made trickier for people who aren't straight, through no fault of their own. Presumably others feel the same about characteristics they have which result in difficulties that aren't their fault.
It's true that reframing every problem to be a result of societal oppression and entirely outside of a person's control would be unhelpful, but failing to recognise those external structures and social issues would also be unhelpful. Sometimes people already blame themselves for things that are at least partly down to systemic problems, and helping someone to see that their difficulties fit within a bigger context, that they're not just useless but are actually operating in a system that in some ways is rigged against them, can be an important part of working out a realistic way through their difficulties.