Right, so your statement “no, everyone who takes amphetamines experiences a state of calmness” is incorrect.

I used the word "nearly" in my sentence, which is not the one you put in quotes. Also, that a given person may experience side effects at a given dose, does not mean that they will experience those same side effects at all doses. Any given person who benefits from amphetamines, would also begin to experience some side effects if given too large a dose. Given this, my original comment could have been more clearly stated as: amphetamines have a calming and focus-enhancing effect on nearly everyone, given a tolerated dose.

not OP. but he did say "nearly everyone".

long lists of side effects are common even for the most benign and common drugs. that's standard.

for example i could say that the common side effects of tylenol[0] tell a different story:

nausea, vomiting, anemia, rash, dyspnea, abnormal breath sounds, pulmonary edema, hypoxia, pleural effusion, stridor, wheezing, coughing, peripheral edema, hypertension, hypotension, tachycardia, chest pain, muscle spasms, insomnia

[0] https://www.drugs.com/sfx/tylenol-side-effects.html