MDMA, when I used it, was always combined with dancing or walking or physical activity. I also always had a coming down which had a bottom peak a few days after (the infamous Tuesday dip). With psilocybin I had not much of a coming down, at worst a headache the day after. With MDMA though, the coming down additionally had my mood being down as well. I become agitated and inward, very much in contrast to the peak and moderate upper effect (there are some movies which portrait this, such as the movie Human Traffic [1]). Then again, this is anecdotal, and I am very sensitive to drugs in general, especially the contrasts (alcohol, beer makes me often tired, MDMA, SSRIs, amphetamine). The reason for that might very well be related to ASD, I do not know for sure though. I just know that I do have ASD. But because I have ASD, my anecdotal experience isn't typical in this case. However the Tuesday dip is widely known among MDMA users.
so known so people use additional things to avoid it. personally i'm also very affected by the comedown. whatever makes everything feel great comes as just a big price in the other direction. this is also the reason that perhaps stuff like depression might make it feel even worse.. and only solution would seem is to do it again more regular.
[1] https://en.wikipedia.org/wiki/Human_Traffic