[jampekka]

Yes, there are some, quite rare, side effects. The visual disturbances of HPPD are quite subtle (ibid.), and definitely not making you blind as you claim. The psychedelic experience can be extremely distressing, especially at high dosages and in difficult settings, and this may cause longer term mental health problems.

Almost all drugs (illegal or legal) have potential side effects. Most psychotropic medicine have quite nasty side effects and/or cause dependence. SSRIs can make you insane or to lose your libido. Benzodiazepines are very addictive and their discontinuation may cause fatal delirium. Eating a box of Tylenol can easily destroy your liver permanently.

Comparably, LSD is pretty darn safe. At least when taken in well controlled doses and in safe settings. Hard to see LSD's side effects being a showstopper for its medicinal use.

Yes, 2C-B and the many many similar compounds tend to have similar side effects.