Nah, the negatives far outweigh that one little positive.
That's a matter of opinion, but anecdotally I know a number of players who use 1v1 to test their drafts before moving to multiplayer (with at least one person who only enjoys playing Commander 1v1 with the normal banned list), so I wouldn't call it a small positive as much as I would a feature of the client.
So many games continually ruined by OP swingy cards that shouldn’t exist in 1v1 (absolutely sick of 5 mana commanders being cast on T1 from
Jeweled Lotus) …….. vs the slight chance to playtest a MP deck in a 1v1 game?
Yes, 1v1 Commander can be extremely swingy, but in your given example if you had immediately nuked the commander that got Jeweled out early suddenly that opponent is down a card from the Lotus and their commander is functionally gone now unless the game drags on into the late game. Fast mana can very easily spiral 1v1 games to an accelerated conclusion, but the thrill of overcoming a Sol Ring, Mana Crypt, or Jeweled Lotus start from an opponent and winning are exhilarating (in my opinion).
Making a whole new 1v1 would be way too bloating because then you could potentially play 1v1 in 3 different ways. There should be a 1v1 for competitive commander (like there already is) and 1v1 for casual commanders (with an actual appropriate banlist)
I think modo is a pretty dense program in terms of learning curve already, and have faith that people who want to play Duel Commander could figure it out if a room was made exclusively for them. Especially since most of the games I see in the Freeform Commander room are already marked explicitly as being for Duel Commander. I know that 1v1 Commander failed previously on modo, but that format was an original WotC idea and wasn't proper (at the time) French Commander. I'd wager that if proper Duel Commander got support it wouldn't suffer the same fate.
I think you'd get support for Duel Commander getting it's own room within the Commander tab of formats, but I don't think most people want 1v1 commander in the Commander Open Play room to have a different ruleset than regular multiplayer commander.