"Sanctions" are just a sanitized way of saying "forced starvation" and "denying basic medical care" because that's what happens. For Cuba, this has been going on so long that the CIA documents about the effect of sanctions and a blockade itself has been declassified (
in 2005) [1]. When faced with a UN report that estimated 500,000 children had been killed by US sanctions in 1996, then UN Ambassador and later US Secretary of State Madeline Albright famously said "the price was worth it" [2].
And sanctions don't actually work. Not against enemies anyway. Just like Cuba has endured 60+ years of sanctions and Russia has endured Ukraine-related sanctions, enemies have or build an economy to be resilient to the sanctions to the point that the regime survives, even thrives in the face of perceived exteranl threats.
Probably the only successful use of sanctions was South Africa. Why? Because apartheid South Africa was an ally so the BDS movement crippled the economy.
And most of the time sanctions have no other reason than the affected country dared to not be exploited by the West and Western companies.
[1]: https://www.cia.gov/readingroom/docs/CIA-RDP79R00904A0008000...
[2]: https://www.youtube.com/watch?v=4iFYaeoE3n4