That's not what a famine is. A famine is when there's no food at all.

Are you three?

In most cases of famine there's food but it's just not getting to the place of most need. That's exactly how every modern famine has played out. That big Ethiopian famine in the 80s, there was enough food in the country but the government was withholding it from people they didn't like. The holodomor was also purposeful starvation of political enemies, otherwise it wouldn't be counted as a great crime. So these things you mentioned could have been solved by simply buying food in off the free market, but that was purposely not fine for political reasons.

The thing you are missing is that at Marx's time capitalism wasn't at all comfortable. That's why he and many of his followers thought it would collapse in their lifetimes. It was actively made more comfortable by liberal politicians who were scared their businesses would go bust and conservatives scared they'd get the guillotine. The workers didn't betray the Marxists, the world changed, conditions and rights improved via political means and the Marxists stood still fighting a battle which wasn't even taking place anymore.