I think, for the VA specifically at least, this isn't accurate. I'm sure they have some phd psychologists around for other things but the bulk of the work you mentioned will be done by counselors with masters degrees and some psychiatrists overseeing them. Psychiatrists, as well as "the -ologists" you mentioned, are specialized medical doctors. They all get the same schooling and then specialize through the residency system.

An MD is a doctorate-level degree and MD + residency is generally considered enough education for even research within a speciality, certainly patient care within it. MD/PhDs are rare, usually doing policy/leadership or extremely specific technical R&D. Almost never see them doing patient care, when you do it's normally because they misunderstood their own career interests in their 20s and now have to live with it.

This thing is real bad but psych treatment at the VA isn't why.

the -ologists can be both, then. My academic experience in ancient times had them as medicine related PhD's, but I guess MD's can specialize in that area from a treatment rather than a research area. MD/PhD's are rare but quite valuable for research projects because they can see patient records wearing their MD hat, but interact with the research teams with their PhD hat. They tend to have mediocre bedside manners cuz they rarely see a bed, and they're sorta burned out coming of all that schooling.