what does it matter? same as being on probation, you've done wrong and part of the consequences demands that you change your behavior regardless as to whether it's "fair" or not
Well if he's just been doing drugs recreationally and has no issue whatsoever with addiction, then it would be heck of a lot harder to sympathize with him here. He knew what the consequences were, and decided he'd take his chances, hurting his team in the process.
If he's addicted, anyone who has dealt with friends and family members who have gone through the same thing knows how the other aspects of their lives (in this case hockey) inevitably fall apart. It's tragic to witness. Of course at the end of the day he's responsible for putting in the work and staying sober, and he's been given all the resources anyone could ever ask for do so. But still, it's not easy and it can take people years to finally recover, if they ever do.
You hope for the best for him, but if you're the Avalanche you probably have to start making plans to move on from him.