I can only say i’m really impressed by blizzard with dual spec, debuff limit and instant mail. As well as chronoboon and even tbc and fresh at all.
It’s a really welcome change after constantly feeling like blizz don’t even look at the forums or are so out of touch with the general player base. people complaining about this minor but massively impactful changes like dual spec are the minority. We will see such an influx of healers now since they can actually play outside of grouped content. This can only be good for the game 
I just hope sweats don’t start expecting healers to have a raid healing and tank healing spec and no option for dps spec (but i believe ofcourse people will use every opportunity here to min max). Maybe they will implement only being able to change spec in cities, who knows.