Let's face it: who likes dictatorships? To overthrone a regime there is a price to be paid and nobody will pay that price unless there is something to gain(i.e economically or geo-political). I'm ok with that as long as it's done right(which was not case with Iraq) but let's not pretend that it's moral to let these pesky dictators die by natural causes.
In a country's case "the cancer" always has to be replaced with something. The US definitely has no working recipe for that, as several decades have shown.
Let's not kid ourselves, the US doesn't pour hundreds of billions of dollars every year into the war effort because they want to fix "the cancer" and the locals' problems. They do it for political and economical reasons (power/influence/money).
Which is why all such regime changes bring no measurable increase in the quality of life of the local people. So then, from the perspective of the local Venezuelan or Cuban, what exactly is the difference between a festering cancer and a replacement cancer beyond looking at other countries getting richer / more powerful by extending their influence into yet another country?
First of all, how do they demonstrate that? It's not like you can go back in time and test what a Bay of Pigs 2.0 would have resulted in.
Secondly, you don't have millions of refugees, genocide and an entire generation not in school, in Cuba. So there's that. Venezuela I don't know anything about.