And that's the point, you don't do genocide if you are too scared/afraid of losing these pixels you love so much.
Flowey said 2 lines (actually, 3) referencing people that watch the genocide route instead of playing it by themselves, and i agree with him....
TOBY KNEW SOME PEOPLE WERE GOING TO BE TOO SCARED OF TRYING OUT GENOCIDE BY THEMSELVES.
THAT'S PRETTY BRILLIANT.
(No, those are not the lines he says)
But yeah, another method is to do neutral first but kill the bosses, spare the random encounters instead, like that you won't be suffering so much on genocide, but really, it's better to get to know the bad/sad/angry/disturbing side of the characters first, then get to the lighthearted tone.
Or else you'll definetly have a bad time.