The autoimmune and autoinflammatory models of CFS are still valid competing models. CFS itself is almost certainly a cluster of diseases.
Viruses are some of the most common triggers of autoimmune conditions. Autoinflammatory conditions can be triggered by all sorts of things, from metabolic to immune. Pervasive latent viral infection is somewhere considerably above 80% in our population. It might be more like 100%. Nobody knows the full effect of this. Metabolic, immune and inflammatory issues are likely to be consequences.
When part of the immune system goes down, part becomes increasingly activated. The immune system operates in what are called axes (plural of axis, not the weapon/tool). Different parts suppress other parts, or boost other parts. When one part goes down, everything it supports goes down a bit. However, everything it suppresses gets stronger due to lack of suppression.
So both hypo- and hyper- immunity can occur in the same person. The immune system is not one big solitary lump. Its a network. Various factors may also boost or suppress various parts of immunity. A latent viral infection will have an impact, but there are other issues that are known including increased translocation of bacterial toxins from the gut. Viruses are also not the only pathogens associated with CFS-like conditions. Lyme disease is one, though now its apparent that Lyme is more a family of diseases, not one single disease. That is one of the factors that can stuff up a Lyme diagnosis.
There is considerable evidence of viral infection, autoimmune responses, autoinflammatory responses, inflammation, immune abnormalities, oxidative stress, metabolic issues (including mitochondrial), cardiac dysfunction, CNS dysfunction, muscle and vascular dysfunction. Models typically focus on part of the whole, or vaguely point to a lot of parts but have one central theme. Most of these factors operate in loops. Problems in one area can cause problems in another. With apologies to Isaac Asimov, when you point at a circle, how do you know when you are pointing at the start of the circle?
Alexander the Great faced a problem like this with the Gordian Knot, according to legend. In myth the Gordian Knot was a massively complex tangle of threads. Nobody could untie it. Alexander the Great didn't bother. In legend he drew his sword and cut the knot. Its a metaphor for thinking outside the issue. Everyone promotes their own little bit, their own little perspective. I keep waiting and searching for that one little bit that will completely transform how we view all this. Nobody knows when that will happen, or in what discipline.
As far as some cases of CFS (not so far as I am aware strictly defined ME) we do have examples of AIDS like problems. Some are diagnosed as having various immune disorders that are typically found in AIDS. A few cases of Karposi's sarcoma have also occured apparently. In the 1980s there was a brief period in which ME was called AIDS minor I think. This was because it looked like AIDS but did not progress like AIDS.
There is no question that most of us with ME have immune deficits. There is also evidence that we have increased immunity. The two positions are not mutually exclusive, even in the same patient.
Bye, Alex