You don’t need every option available to create a character you can have fun with, and if you do I’d ask you to consider and answer me why do you need every option available to have fun?
I expect for many, it isn't that "all options need to be available to have fun".
I know many people who come at the game character class/race concept first - they make up and become attached to concepts before anyone suggests a game. So, if you start changing the races and classes available, they will tend to have their desires cut off.
Others may have a desire for consistency across the various game options available, as a game design element.