No commander cards in Brawl?

I'm late to the party here, and I'm sure there's a obvious reason/history I'm not aware of... but why does the card pool for Brawl leave out commander cards?

Recently I bought a strixhaven precon and having a freaking blast playing it. Got an itch to try it out online in Brawl since I heard it's commander(ish). I know its a different format and heard not all the cards would be there. And never tried it before, so was gonna import my precon and just replace whatever cards weren't there...

...I soon come to realize, there is pretty much no commander cards in here. I am happy for all you Brawl enjoyers out there, but that instantly killed all my interest in ever trying it lol

Just seems... odd to leave those out of the format. What's the reason commander cards aren't in Brawl?