I think this is simply a numbers game. Amiga had around 4000 officially released games.
Megadrive and SNES only had around 800 each.
GIven the ability to monitor quality control on the proprietary console formats then it's a no-brainer that far more dodgy games would be released on the Amiga. I would wager that the Amiga also had more great games than either console.
I really don't think the top 50 games on each platform would show the Amiga to be inferior. Just different.
The Amiga version of Rodland was an exquisite platformer.