I wouldn't say most, maybe a little under half, and usually these are pretty minor effects that don't bother the person very much, and for the most part seem within normal subjective variance, just perhaps jarring because of the change. I wouldn't be surprised if there are some extreme cases, but it's kind of alarmist to view it as ultra scary compared to even the effects on your adenosine cascade from persistent caffeine use. I haven't personally had any of these despite having tried a number of psychadelics, and I get the mindset that anything that could be permanent sounds like a pretty serious risk, but as harms go this is quite negligible in practice.