For example hate speech could be restricted, supported by a majority of for example 60%, whereas the hate speech would only be exercised by for example 10%, endangering a minority of 5%.
Those who actually argue for more authoritarian elements, for example those who'd like Trump to not be hampered as much by the judicial system, don't really want "authoritarian"-ness, but rather they want the government to do what they want. They don't seem to realize that once a government has those powers, they have no control about what the government actually does. When a sufficient majority is buying into this, and actually wants to enact the same things, it's game over for democracy.
However, most authoritarian governments didn't develop that way. Most seem to develop by some people just taking power through various means and not really through appealing to a large majority.