my experience Tl;dr  :
1. marijuana is IME 30-150 times stronger painkiller than anything otc, opiates, perhaps 50-1000 times
2.  if you get injured bad on marijuana you may not notice till it wears off.
3.  trillion dollar criminal industry so they will tell lies and make up anything, or purposely injure people to have life-long customers
4.  Marijuana is said to be a 'gateway' drug.  when i smoked a dealer who sold me some purposely tried to severely injure me, i believe this was to force me to need stronger drugs, i dont believe it commonly leads to abuse of other drugs without some other factor in other words.

will finish later