No, Jokes are not by nature bad, They are meant to be light-hearted, A means to interact or perhaps even a coping mechanism not to mention that they add colour to life and are a means for individuals to express themselves. To take away jokes would suck the very little joy that life has to offer
This is like saying that a basic human emotion is not good and should be illegal just because you didn't like that someone didn't do it on your joke but did it on theirs. If jokes were banned, So many people would be locked up in jail, Jokes would become a basic drug- not to mention people would take drugs for happiness, And the country would collapse within days. End of discussion.