Monopolies can only exist with government support via protection from competition. Expansive government power makes monopolies more likely and more stable than minimal government power.
I'm not sure what you really mean by "monopoly" or what sort of monopoly you think can persist in the absence of government support.
Note, I started my participation in this thread by advocating for minimizing government, which is not the same as eliminating government. So I'm not trying to assert an absolutist position that free markets should have no regulation.