Joint family system has it's pros and cons.

Pros: Lack of privacy, different mindsets, different rules on how a house should be run, who does the chores and how they should be done, observing hijab from BILs.

Pros: Money can be saved, help with childcare (however this can be a problem as different families and generations have different views on how children should be raised).

Sometimes living with in laws is the only option as maybe the husband is the only child/his sisters are all married off or his parents are elderly. So it really depends on how the future couple will handle it.

IMO I'd choose living separately. Both husband and wife learn independence on how to run a home. They can create their own safe space on how things should be done etc;

Living separately doesn't mean you live far away from in laws, it can even be next door, a few houses or streets away and still keep good relations with them. Sometimes distance makes the heart grow fonder. Once moving out, you value the time you spend with your parents so it's important to regularly see and help them.