Stance dancing has never been a required component in 90% of the game's content. The tooltips themselves suggest that tanks should only "switch stances" when they're in the offtank position, and that's what the traditional MMO tanking paradigm has been.

So seeing someone "sit in their stance" the whole time is not a bad thing. In most cases, it has never been a bad thing.

Alexander Midas also changed things a bit to my understanding, where tanks are having to soak a good deal more damage, and to where groups are failing mechanics more than failing DPS checks, so staying in Tank stance is beneficial when learning a fight, and when learning when to expect spikes of damage. Doesn't make them bad.