I would say that a big part of the problem, in places like Venezuela, is that income distribution doesn't look anything like a bell curve. I'd guess that it probably has a very big bulge down near the bottom, a fairly low level through the middle incomes, and then a smaller bulge up at the higher end - i.e. big mass of desperate poverty, a small to moderately-size middle class, and a few ultra-rich. That's what makes so many people willing to embrace radical revolutionary thinking in a place like Venezuela.
OTOH, the income distribution in the US, for example, probably is more like a bell curve, and socialism does appeal to those on the left side of the curve, but not strongly enough to enough people to engender support of a Marxist revolutionary.
Marxist socialism takes root easiest in subsistence economies. Look at Russia and China, for example.