I feel like this is just a bad troll attempt but I'll bite anyway.
M&K is best for precision aiming. So it's ideal for games like Bioshock, Call of Duty or Overwatch. I'll use a controller if I'm playing something on an emulator like Mario Kart or Breath of the Wild. Controllers are better for racing games. Any PC gamer will tell you that. You can even switch on the go while playing GTA V.
PC is about choice. I choose what I want to use. I choose what games I want to play. I choose how I want to mod my games. I choose to play with better graphics and frame rates. When you buy a console, you are limited to what that company wants you to play, how to play it and the settings are restricted because Consoles in the last few years have basically been low end to mid range PCs. And mods? Forget it. Only a couple of games support them and there's a limit to how many mods you can use.
Lastly the catalog of games for PC is massive because you can play the older games as well as the new. Not to mention all of the exclusives.