The period will eventually push through.
Tho I’d say the main reason all women of the world don’t use it is because birth control has side effects that can be very severe. Think mood swing that leave the person suicidal. A lot of the less severe side effects might still not be worth it depending how bad the period would be. It might be painful, but just for 4-7 days, whereas birth control side effects are 24/7.
You have to opt-out. I got an email from meta with a link to the form. Doesn’t seem to matter really what you write. It got approved in less than a minute for me. I think they purposfully made it look like it’s more work than it’s worth.