I have never tried heroin because at the time when I learned about it, I looked at some information and came to the conclusion that it would not be a good decis

I have never tried heroin because at the time when I learned about it, I looked at some information and came to the conclusion that it would not be a good decision to make given the physical addictiveness of the drug. To be honest, I attributed almost zero weight to the fact that it was illegal. Remember, opiates are legal now, with a prescription. I wonder, hypothetically if there was a drug where the effects were as pleasurable as I assume heroin must be, but with no physical addiction or nasty side effects, would people still be against it? What if, in the future, your cellphone could emit a frequency that generates pleasure in your brain, but as soon as you turn it off, you are back to normal. Would that be made illegal? Could it be simply a moral objection to unearned pleasure that people are really against?