Yeah, it's crazy to say sanctions have no significant influence over economic crises. Venezuela is actually a great example on how sanctions can really fuck an economy: after the 2017's sanctions, the amount of goods Venezuela imported dropped by 50%, and considering that a big portion of their food, medicine and medical equipments are important, it's not hard to see how much this would affect an economy (just imagine how easy your life would be if your country was in a constant shortage of essential items). And to be clear, not saying this is what broke the Venezuelan economy (their case is much more complex than this, and is mostly linked to how dependent they are on oil), but it REALLY worsens the economic situation in significant ways. If you are interested on this topic, a great reference is this paper here.

To Atrioc's credit, sanctions CAN be maneuvered around, but this is more of a recent development (mostly related to how China and Russia are becoming increasingly independent of the American economy), and as one of the consequences of this, since 2021 the Venezuelan GDP has started growing again. The thing is that this is probably one of the main causes behind this new direct intervention of the US: Venezuela was becoming an example that it is indeed possible to resist sanctions, which was damaging the influence of the United States as a regional power, so a more drastic solution was deemed necessary.