Here is a randomized, triple blind study: https://pubmed.ncbi.nlm.nih.gov/34562208/

”had significant positive effects on brainwaves, salivary cortisol, and self-reported state anxiety compared to the placebo in response to an acute stress challenge. These changes are indicative of relaxation in the brain and suggest a calming response in a moderately stressed but otherwise healthy population”

n=16. This isn't even worthy of classifying as a Phase I trial. Efficacy studies generally _start_ at n=100. Drawing any conclusions on efficacy from this kind of sample size is simply unscientific.