All culture is peer pressure.

It's just that our culture has laxer consequences for unacceptable behaviour and less expectations of personal responsibility.

What constitutes worse is a matter of opinion (a.k.a. norm), in US culture women can have their rights and access to healthcare taken away without consequence to the oppressor.

Even in matters of personal honor, the rapist-in-chief famously has little to no consequences for besmirching his own and others' honor, exemplifying many other such cases.

Harakiri and shunning can be argued as better mechanisms to protect women.

It's just different solutions optimising for different outcomes. And many solutions differing from our own have shown success for certain goals, be it US, China, Islam, Catholicism, Roman or Aztec.