Iranian tanker docks in Venezuelan port

Venezuela's oil is probably among the worst on earth to refine into gasoline (and that obviously would not help the situation during sanctions) but when things are going well it is still easily handled. Iran's oil is perfect for making gasoline.

To put into perspective the amount that arrived on these tankers, Iran did not send their best, they were crappy hulks that did not have much capacity. Large tankers (mundane large tankers, ) easily surpass the amount these five ships put together brought (by a considerable margin) but at least the first one made it without any problems. It looks like crap. Like a garbage scow. But it survived to make it and Iran did not risk a valuable asset, and I am sure that was part of their strategy.

Venezuela's oil is probably among the worst on earth to refine into gasoline (and that obviously would not help the situation during sanctions)

Citgo not refining Venezuelan oil hurt. Russia and China have refining capacity; both nation states are heavily invested in Venezuela. Russia's expanding the global reach of its Eurasian Economic Union, China its Belt and Road.

Way passed time for the US, Chinese and Russian empires to shift farther from a fossil economy. Way passed time for each to become more self-sufficient and leave other nations and their resources alone.