In this design, I have to imagine both groups' sessions were very much affected by thoughts of "am I about to trip or is this just allergy relief?" To be honest, I am uncomfortable with the thought of a participant being unsure if they had been given a psychedelic.
Consider that a non-trivial number got it wrong! To me that signals some of the control group participants may have been quite agitated.
I wouldn't mind seeing a self-controlled design where participants are randomized to receive either psilocybin with therapy or non-psilocybin therapy first, but ultimately end up receiving both. As others have noted it's not just the drug, it's the drug and the experience of therapy so I think the two ought to be packaged.
Ultimately though, what I am most curious about is the long term sustenance (and/or repeatability) of any effects and also whether any negative effects appear later.
The first wave of psychedelic research also showed some promise, but their utility faded. Have we gotten any better? Six months of alcohol use disorder or depression relief is great and useful, but the goal ultimately is long term relief.
They have a good point. The whole “chemical imbalance” thing has come under significant scrutiny as of late.