These sort of things happen all the time in game development, especially in older games. Some games don't have room for everything that the developers want to include. For that reason they have to remove cool features in order to fit what is most necessary for the game to be played. In this case Mario was supposed to feel actual love for the world surrounding him and all who inhabit it. He was supposed to express these emotions not just verbally but also through genuine acts of kindness and subtle yet affectionate forms of touch. In theory his outwardly flowing love was supposed to reach you, the player. Creative Director Shigeru Miyamoto admitted that there was no room for Mario to feel love because they needed to somehow fit Bowser in. "If Bowser's not there then we don't know what would happen next." After hearing about this it really makes you think how different of a game Super Mario 64 could have been! A game where the main character feels love for everything around them AND Bowser doesn't get in the way of anything? Yeah, as if that'll ever work. In other news Nintendo is celebrating it's one year anniversary for Animal Crossing: New Horizons this Saturday on March 20th!
