Paper Mario and its sequel, The Thousand-Year Door, were brilliant RPGs with a brilliant cast of characters full of personality.
Super Paper Mario was a gimmicky platformer, but it kept the same feeling with its characters and dialogue.
Then Sticker Star happened.
Sticker Star drained the series of any and all personality, even making Bowser a mute, and completely gutting the RPG gameplay. All your attacks became one-time use items. From the basic jumps and hammer attacks to the special attacks, you could do nothing without stickers. This forced players to avoid combat in order to preserve their collection of stickers. What's more, each boss fight in the game required the player to obtain a certain sticker to make the fight trivially easy, or they're faced with an hour-long grind against an enemy with impossibly large HP and attack power totals. What's more, if the player takes the more challenging route, the game flat-out calls the player a retard.
In spite of the disaster that was Sticker Star, Paper Mario fans held onto a tiny glimmer of hope that maybe Nintendo would realise that people liked Paper Mario for what it was, and would allow Intelligent Systems to make an actually good game.
Instead, Nintendo proceeded to take a shit in the collective faces of anyone who enjoyed Paper Mario.
Rest in peace, old friend.
We'll always have the memories.
No matter how Nintendo decides to parade around your lifeless corpse, I will always look back upon the good times fondly.