I agree it can work. A group I was part of in Austin in the 1990s implemented a rotating DM system. It worked for at least 3 years. It was still in place when I moved back to Dallas.Do you really think this can work? Yes, I absolutely do. Am I brimming with confidence? No, I am not.
How we made it work:
1) it wasn’t all in one campaign. Everyone was responsible for running a campaign, and had to have a PC for each campaign.
2) the campaigns were not all in one RPG, but rather, spanned dozens of systems.
3) each week, two people were charged with being ready to run a game every session- a primary and a backup in case the primary couldn’t run their game. This meant everyone also had to bring two characters (except the GMs, who each brought their PC for each others’ games).
4) if neither GM could run- rare, but it happened- we had a pre-selected board or card game that would be played.
That system was VERY effective. We tried DOZENS of different RPGs, including a couple of playtests. Some campaigns ran for years. Some GMs never ran a campaign to completion, and instead, kept wanting to try different games…often within a single genre.