Whats the alternative? Having no content for mythic raiders?
For people playing much, but only 1 or 2 chars, there is NO problem. They can login whenever they want, do stuff they wanna do and so on. Even gearing alts is easy, via m+ you can be ilvl 900+ within few days.
Problem is for those wanting to maximize 5+ specs/chars . Maximizing for nearly no gain is a selfmade problem. Having to care about 4+ chars, running mythic NH on 4 chars, thats a selfmade problem by a hardcore playerbase.
It could be good for the game if world first races werent that extreme.