There’s been a little back and forth on the changes this season to how dungeons are classified and their difficulties, and without belittling the opinions of anyone else, I wanted to say that I think the changes are great, and an overall benefit to the game and to the majority of players of the game.
Moving heroic dungeon difficulty up to the level of what were previously Mythic 0’s gives people the option to queue up for that content in the LFG tool, allowing easier access to that level of difficulty and the rewards of that difficulty. By deleting the old version of heroic dungeons blizzard is creating an environment where the distinction between normal and heroic is noticeable in terms of difficulty and in terms of reward, especially for the more casual players who are likely to spend a lot of time there. By moving old Mythic 0 difficulty/rewards into the heroic category, blizzard has removed confusing clutter and given more casual players what was often asked for: the equivalent of queueable (old) Mythic 0’s.
The more controversial decision they made, however, was to basically remove M+2 through M+9 and turn M+10 into the new Mythic 0. As a result of this, a lot of people who were previously running single-digit Mythic+ dungeons have hit a point that feels (in this first week) like something of a road block to them. While there are a lot of complaints now, I think the majority of this is just the result of the current situation not meeting the expectations formed from their past experience. Not everyone read about these changes ahead of time, and some people may have been blindsided by them, and that will subside in time.
Overall, I think this more controversial change is an even better decision than moving M0’s into the heroic category. By making the new M0 the equivalent of M+10 in the past, Blizzard is definitely creating a significant challenge for people who may have only been running single-digit M+ dungeons, and one that might seem unfair at first glance. But because there is no timer on Mythic 0’s, these are difficult dungeons that can be handled more carefully by less geared or less skilled players. Like difficult old dungeons very early on in WoW’s lifecycle, these are dungeons where players can once again use hard-CC to deal with big packs if they need, can use tactics to split up groups or kite and slow units as needed, etc, in order to accomplish their goal. It’s a sort of small-group endgame content for more casual players who want an older-style WoW experience.