The 40,000 Commander decks introduced types like Astartes and Tyranid
Here are some criteria to look out for when picking a combo-based commander: Synergistic color identity
From here, it slowly declined to ~2 USD, where it has stabilized and been for a long time
However, Bears are still a powerful type in their own right and can do a surprising amount of damage with the right Commander
They may never come in untapped, but that downside often isnt actually a hurdle if you carefully time when you play a mana ramp spell or fetchland
In Premodern, its kind of agreed on, I think, that the best white and black cards are Swords to Plowshares and Cabal Therapy