Not really sure what you mean by global best practices. The arguments people are making for them make very little sense to me and probably make as much sense to the average person who doesn't really care how the doors open they just want them to open when they get off. The people who think it's good have probably never seen someone who is frustrated about the door not opening and they don't want to be told to push a button to open it. There are many times when I've been on buses where the driver doesn't unlock the back door of the bus so that someone can push it open, it's far simpler to open all of the doors then it is to make people do something extra that they may not understand or care to do.Because Toronto exists in an alternate reality where global best practice does not apply.
Who knows I could be completely wrong and they will make people use the stupid buttons that everyone in Europe seems to love and we should use because we are behind the times. The only time I could see them being used is possibly during non peak times of the day and probably only at the outside stops which will probably confuse people anyway who aren't already confused about having to push a button in the first place.