The more research is done on the placebo mechanism the more likely that eventually some scientist is going to mention to the research team that they know a colleague who has been showing very similar results at ameliorating psychologically-entrained stress using 'a new drug'.
Hopefully enough scientists who would never have considered researching morally hazardous drugs will be brought to the mountain by other, more circuitous routes.
Having the psychedelics conversation with anyone invested in 'normal' society, scientist or not, is usually impossible due to their conditioning. And why would any rational person risk their career when everybody, especially their contemporaries, knows drugs are bad, regardless of what they personally believe.
I think this is very much like other socially dampened intellectually activities. Once the leaders have cleared the way and slowly accrete support from the scientific community, it's really only a waiting game for that support to reach the critical mass of slightly more than half of the group before you will not be able to find anyone who ever didn't support the research.