It's been covered by many articles. Most games never came to a satisfying conclusion and ended up dragging on and on. The number one point most people come to is that house rules always ruined the basic gameplay.
To be honest, I have never played a game of Monopoly that didn't feel like it dragged on and on. Even without house rules. Imo, it is just a dreadful game, where the winner is decided pretty early on in the game, and what follows is just a long drawn out crawl towards the inevitable victory of that winner.
Arguably, this is what prompted Monopoly Legacy; a variant of Monopoly that is all about switching up the rules, and changes to the game being permanent.
D&D never stated that its rules are law. They are guidelines. Most DMG's for example explicitly state that the DM can choose to not make use of magic items at all, for example.