that the word 'communism' is universally understood as referring to the state owning the means of production, whereas the original term 'socialism' is used in multiple different meanings nowadays, but most commonly the way in which all the mainstream-left parties in Europe with the word 'socialist' in their name, as well as those young Americans, intend it. 'Poorly educated' is just sour grapes from you.
Of course I can't say that using socialism in the original sense of the word as you insist on doing is wrong, but if the goal is to make yourself clearly understood, there's a better alternative. If the goal is just to score political points for domestic American consumption by trying to associate Bernie Sanders or single-payer healthcare with the mess in Venezuela, well, carry on then. That's basically what I meant with the comment about leaving the right wing radio stuff at home. Not that I was or am expecting you to agree with that point of criticism.
As for the point of principle there - I would encourage people to use words correctly, sure, but when so many people have started using a word in a different sense from the original one that the newer meaning is the dominant one, I'm not going to stubbornly keep insisting. The meaning of words can shift over time, whether we like it or not. 'Irregardless' is pretty idiotic to you and to me, but there may come a time when it's commonly accepted English.
I would go further and say that most socialist parties don't even seek to implement your definition of 'socialism', i.e. full state control of the means of production (though they may advocate state control of some specific sectors like public transport and healthcare). Which just so happens to be the primary characteristic that the world's communist regimes have in common (if I understand your reasoning, you're saying in fact the world hasn't actually seen any communist regimes, yet I dare say you understand to which regimes I refer). Hence the shift in meaning in most people's understanding of the two words.