I'd expect a more robust defense of personal privacy from a "rationalist", because this reason is bunk, and everyone in modern mental health knows it. I've worked as a clinician in the types of settings Mr. Alexander works in (locked inpatient psychiatric units), and others in mental health as well, and while there's certainly a longstanding debate within psychotherapy (talk therapy) about so-called "self-disclosure", the days when clinicians were expected to be "impenetrable to the patient" and "reflect nothing but what is shown to him" are long over.
Researchers and practitioners from nearly every therapeutic modality that rose up to challenge (and in many cases mostly displace) these leftovers from Freud have challenged the notion of "psychiatrist-as-cipher" from within their own perspectives. And there's even a very good case to be made that hiding oneself as aggressively as Freud wanted clinicians to do (and as aggressively as S. Alexander seems to want to maintain) only augments an already severely lopsided "power dynamic" in the therapeutic relationship. In plain English: it's attitudes like these that allow "the therapeutic class" of which I am a part to lord it over the populations we are ostensibly treating, people who in many cases aren't treated as people and who have valuable expertise and experience in matters relevant to them but who we, historically, have been eager to ignore.
But it's funny because these debates have occurred within the universe of "talk therapy", a universe that psychiatry as such abandoned about fifty years ago. Dr. Alexander is a psychiatrist in 2020 - not a psychologist, not a social worker, not even a nurse. His profession left all pretense of actually talking to patients behind when they fully embraced medications as the first-line treatments for nearly all mental disorders; psychiatrists today do "medication management".
None of this is to slander the guy, by the way; he's really good at what he does (the blogging, I mean), and I've enjoyed a lot of his output over the years. But this specific reason for remaining anonymous got under my skin a bit, because it's wobbly for the reasons I listed. It's _also_ wobbly, I'll add, because the rest of us in mental health could have no such luxury of privacy these days even if we wanted it - and 99.9999% of us do not maintain ultra-popular and highly public-facing blogs. I value my privacy greatly, perhaps more than Alexander, but citing ancient and highly contested professional mores to maintain it is pulling a fast one on the public he very much needs right now.
It's bunk to call Scott's concerns bunk. You may think that he ought to self-disclose, but that's simply not his call: he has a job as a psychiatrist and has to stick to what his employers require of him if he wants to keep working in the field, and support his patients.
Further, to cite that as his first reason for wanting to remain pseudonymous is odd, because it's flimsy for the reasons I cited. His second reason (that he's gotten death threats) is much more compelling, and to me is all he needs to make a good argument here. Why sully it with things like this?