Obviously.
I think you're misrepresenting Chris' love for Tony and underestimating the loyalty aspect Chris is constantly questioning.
It took longer than it should've for him to be made. He was already doing things a made man would and when you factor in his dad, and his relationship with Tony, I could see why patience would be hard to come by.
As far as the heroin and alcoholism, let's face it, everyone around him wasn't very supportive and at times, harmful to his recovery after rehab.
And so what about the revelation at the accident? If you're saying it would've been inconsistent for Tony to have not done what he did, then I'd agree. Otherwise, all Chris said was that he wouldn't pass a drug test and could lose his license. Just in the previous episode, Chris got too drunk at a party with everyone while Pauly was fucking with him. So it was obvious he was already dipping in and out of sobriety. Tony just couldn't find a role or way for Chris to be in the mob as a recovering addict/alcoholic and that spelled the end for Chris, imo.