I firmly believe a lot of current mental health issues are worsened by living under capitalism, as do others. Some of the most obvious examples to me are:

• Anxiety about being able to afford food and housing, having a stable job, not having emergency medical events, etc.
• Depression from not having free time due to being overworked, or from not being able to afford entertainment and distraction, etc.

One potential remedy to mental health issues has been developing in the form of psychedelic therapy. Besides the issues related to restricting access by making the treatment prohibitively expensive (both the drug and the administering physician) that are seemingly unavoidable in profit-driven healthcare systems, I think there's a massive danger in using psychedelics to effectively pacify people.

Psychedelics can be used maliciously, in that they can be used to help people accept their life as it is--this sounds fine, until you realize that it can be used to make people accept being exploited and being effectively destitute. I think the problem here is that the medical institutions (and probably most patients) are going to have the goal of: being less depressed, less anxious, etc. If psychedelics were actually used to "wake people up to their reality", they'd probably become more depressed, more anxious, etc--counter to the stated goals. I think one of the first steps towards wanting to change the existing system is seeing the flaws in the existing system and how one is negatively affected by it.

Then, if psychedelics are (going to be) used to pacify people suffering under capitalism, is their widespread adoption not a bad thing? If people are willfully blinding themselves to their suffering, is any hint of revolutionary spirit being extinguished?

I don't think these issues are unique to psychedelics, either. If existing depression treatments numb you to all emotion, good and bad, they can make existing while being exploited more bearable.