This mindset is unfortunate, and detrimental to patients. There have been a lot of studies on CBT/GET, and there isn't really any doubt that they are moderately effective. The only issue I have with the treatments is that the theories behind them (deconditioning and abnormal illness beliefs) don't really have any evidence. I suspect they work for other reasons. However, that shouldn't be a reason to completely reject them.

I was speaking to someone recently who recovered from CFS (after being mostly bed-bound) through CBT and lifestyle changes, and she is now completely recovered. In her case there were a lot of recent traumatic experiences which contributed to her illness, so CBT was very helpful in addressing those issues.

Some charities, such as Action 4 ME, seem a little more open-minded about CBT.