The mob cannot fringe upon the rights of others.  Democracy descends into populism when the mob decides to punish those who disagree with them (i.e. the French Revolution) or to scapegoat a specific group of people and use democracy to harm others (i.e. the modern alt-reich).  We don't have pure democracy to prevent the tyranny of the mob.  People are allowed to have unpopular views or practice a minority faith without being killed or jailed for those views.  People who belong to a minority ethnic group should be allowed to exist peacefully in society.