Well, frankly, it doesn’t do much, other than disabling you from getting Oozaru, Golden Oozaru, and SSJ4. If you want to get rid of your tail, it’s fine, mostly just for aesthetic. Or, if you don’t like the color of the tail when you transform into different types of transformations. I personally don’t like the color of the SSB tail, and think the tail should stay the same color no matter the transformation, but that’s just me. Either way, long story short:
You shouldn’t, unless you don’t like it, then go for it.