Thank you for opening this discussion ! I was really afraid to propose this idea here...
So to add my view, that some might not appreciate, I would say that the first base of the game was not really a failure or a disapointement, but it was decided by the highest heads of Nintendo that MP4, with every possible artistical direction and code optimisation, the game would just look ridiculous with a release on 2020 compared to the very last 8th gen games and the coming trailers and demo of the 9th gen. So they scraped it to restart with a more powerfull structure.
Or a softer hypothesis : they scraped it because they wanted a full use of the capacity of the Switch Pro coming soon.
Current PB on Secret of Mana remake : 2h27 (2nd)
Strongest worldwide achievement on TGM : 1st European S13 rank
WR on TGM alternative mode : Fastest ITEM S9 rank ( <-- Just got massacred by the 2nd most powerfull player in the world )
Current PB on Power Ranger (Game Gear) : 10min06 (World Record)
Non-geek activity : ThermalHungary