I've spoken to JP about it over email - I was a first round Exodus investor last year on BttF.
He doesn't want to waste time adding a holder token for a coin that hasn't been designed yet and has high fees on the BTC chain; he's focused on ERC20 tokens because they are 'currently eating the world' - his words.
Exodus is actually already compatible with omni and all omni assets in the back-end. He did the work for it last year, but said he doesn't agree that it is a good one to add now. He said he gets relatively few requests for adding maid relative to other coins. I think the hype train is what pushes them as much as anything, so MAIDs time will probably come.
So, if you want it added you'll have to make your voice heard