Are you mayhap mixing up polearms and staffs?
Not that I was aware of staffs being DEX weapons ...
Possibly but I can tell you for sure I've never been at a table with a Brabarian or Fighter or any other STR focused class that opted to use a polearm. As far as I can tell polearms are largely dead weapons.
What...? Polearm Master + Sentinel is extremely popular, and if you can get in variant human for GWM added to the cheese, even better. Tons of builds use polearms, including one of the most popular ways to build melee warlock but there's also a lot of cheese to be had with 1h staff or spear with a shield and Polearm master.
Granted, if all you care about is Ung Ungh, Big Number, Big Damage, Ungh Ungh, of course you'd stick to the boring, utterly overused weapon types (great sword) for builds and pretend like GWM is the only feat in the game. But a lot of the more advanced players or people who like playing what amounts to tanks or battlefield controllers adore polearms, and as I said, polearm master itself is a very well-known and used feat.
