MaxPass worked well at DL for a number of reasons but part of it was also that it was with Legacy FP still existing there at DL and you could use the FP kiosk at the ride if you wanted to or book a ride via the app with MaxPass. MaxPass basically added the app component that WDW FP+ had, you could make selections on your phone, you could then pick up cancelled selections which were not something Legacy FP had. because MP used a different pool of ride time availabilities so if you cancelled a selection it went back into the pool for someone else to pick it up if they wanted to.
You purchased MP either as part of your park tickets or at the gate but no selections could be made until tapped into the turnstile. There was a downside in that if the app crashed then MP became useless. That happened to us on one of our days and they shut off the ability to purchase it several hours after park opening due to that.
But
Genie+/ILL removed Legacy FP from DL, Genie+/ILL by most accounts still works better at DL than it does at WDW due to a few differing rules and different clientele. I don't think there's any going back to Legacy FP going back to DL.