The sanctions have real, tangible practical effects. It's not just about making them suffer. For example, Hezbollah who are almost exclusively funded by Iran, had their budget cut by half [0]. The military operations Iran undertakes in Syria which are intended to strategically threaten Israel have taken a cut.
It's hard to justify supporting proxy wars when the population at home is hungry.
Hezbollah was created to expel the Israeli invasion in south Lebanon. [1]
One thing is for sure: Middle East politics and history has no single (or correct) perspective.
[0] https://www.thedailybeast.com/as-iran-us-tensions-rise-with-...