I came across this 4chan post again and wanted to add it here for future reference. A very insightly look at the way these two sites operate, as evidenced by their user base.

You see, the problem with Reddit is that it works on the basis of encouragement rather than on the basis of hostility (as is the case with 4chan). When you feel welcomed, your mindset changes and that’s why all cults first try to make the person feel good and wanted before radicalizing them. Reddit will only stop being a disgusting and pitiful place when the people there understand that calling others faggot and retard is essential to maintaining the mental health of their members.