Maybe bias for “no sanctions” is due to modern era of “free trade”. This is reflected in statements “sanctions do not work” that are to be proven or disproven. This free trade era is due to having a large number of countries that are not at war with each other. This bias is not applicable to unfriendly countries, and we need to analyze the issue on merits. In your life, when you have a choice between a nice store owner and business partner and a bully, you would surely choose the former.
What is the reason NOT to have sanctions and strengthen a bad regime?
Cigars? You need to vacation there? Access cheap health care? Drive a vintage 1950 car?
A possible case may be made that trade will make life of Cuban people better and, maybe, eventually a better regime. Here is where I would trust the Cubans on what is a better option.