If it were an officially-recognized idiom, that would go a long way. Currently, the most popular spelling of an empty set is set(), and that’s its repr. If the repr for an empty set became {*()}, that would put it into people’s view.
{*()} has the huge advantage that it works all the way back to Python 3.5, whereas proposals for new syntax will require that you only support new versions of Python. That’s going to impede uptake.