I have no idea what you mean by people "apologising for drug use". But I disagree fundamentally with what you are saying and advocating. And to be clear, I do not take nor have I ever taken illegal drugs (and to be honest, I am deeply concerned about the doling out of legal prescribed drugs without adequate consideration of impacts and damage).
It was not drug use per se that led to this appalling crime. It was the fact that the sale of certain drugs is illegal and is therefore firmly in the hands of criminals. Prohibition of any kind has been repeatedly shown to have absolutely no impact on the availability or sale of prohibited items; its only impact is to place the market for the items in the hands of criminals, with all that that entails.
There is only one way to change that, and that is to find a strategy that decriminalises drugs. I am not in favour of advocating widescale availability - we currebtly have far too much easy access to a wide range of drugs including recreational drugs (like alcohol). Personally I would legalise all use of drugs, and make most (except, perhaps, for the most dangerous ones) available for purchase through the NHS. I would have them sold at a market price - between the purchasing power of the government and trade deals with supplying countries we could reduce costs to well below that which criminals can offer, users and addicts would be better monitored and supported and the profits made could support better drugs and addiction services.
This would also have an impact on drugs related crime - given the amount of lower level crimes like burglary that are driven by the need for money to buy drugs, these would also reduce in number. And it would equally have massive impacts in supplying countries, because we could use economics to support and control the growth / manufacture of supplies, through offocial channels, and suddenly the big cartels have no drugs business - that would free many communities and families abroad who are held in trall to the big crime syndicates.
The bottom line is that we have tried making the supply and use of certain substances illegal for centuries. It hasn't worked. It will never work. The definition of insanity is doing the same thing over and over again, and expecting a different result.