The reason being, you can cast your rituals during your main phase, but then you can't cast Savage BeatingSavage Beating until combat, when all that mana will have drained from your pool
The only reason Zulaport Cutthroat beat out Blood Artist is that it is a 1/1 rather than a 0/1, and has three creature types that can all work well in black Commander decks, over Blood Artist's lone Vampire typing
These sorts of Jund decks have been a staple in Standard for years, and its difficult for a deck full of small creatures that need to work together to win to beat a monstrous pile of removal and unbeatable creatures
However, Grist is also a 1/1 insect creature as long as its not on the battlefield
Neither are ideal or complete solutions, but they would at least allow us to enjoy (a form of) Commander on MTG Arena sooner than having to wait for the entire catalog of relevant Magic cards to be uploaded onto the client
However, the more cards you have in your deck, the lower the chances of you drawing your best cards