Strongly disagree, though I'd never downvote you for that.
Why did the US go to such great lengths to hide its involvement? You might answer that the US's checkered past in foreign policy (coups, assassinations, drug wars, oil wars, supported rebellions, etc) will make the world suspicious despite our altruistic intensions here. But I think the rest of the world's answer is simpler and more likely: our intentions are not altruistic, and this is merely another unprincipled application of power to obtain a goal. That checkered past is good evidence, and there's no reason this is different just because "social media" is a magic word or something. For example, why are we trying to undermine Cuba's regime but not Saudi's? Because our policy goals only pretend to care about dictatorships. And if we care so much about the Cuban people, why do we have a trade embargo against them?
Which is why no one trusts us and, frankly, shouldn't trust us. Building a platform that you'll use to "push them toward dissent" isn't providing a medium for free thought and reform; it's psychological warfare. We're trying to capture the attention of people and then trick them into doing what we want.
"So what?" you say. "Even if the goals are selfish and strategic, democracy is still good, and Cuba would clearly be better off without a dictator." That's certainly possible, but I doubt it. For starters, our involvement taints any actual emerging democratic movement with the notion that it's just another arm of US foreign policy. I'd like to live in a world where an asshole strong arm dictator can't blame "US meddling" for any unrest without being dismissed out of hand, but sadly, I don't live in that world. So we're really undermining that goal by playing directly into the (mostly correct) notion that the US isn't looking out for other countries' best interests. Maybe we should stop trying to interfere everywhere, because to the extent that our intentions are good in the first place, we're no good at it.
But more importantly, it's not really clear that actual democracy is the natural result of this kind of thing. If driven by US involvement, will a grassroots rebellion against the Cuban regime actually result in an open, honest democracy or will it devolve into a feeding frenzy for US interests, led by US-friendly politicians pushed into place by US operatives? The US has installed enough dictatorships and phony democracies for me to think this is more likely. When you use democracy as a veneer, I'm not sure why you'd expect it to really work.