If those of you who talk about this are Indonesians. So I think you will know that actually Indonesia has long banned adultery or having sex outside of marriage. even in the source you linked it was also explained that the law regarding sex outside of marriage had existed before but was not enforced. and the new law has only been slightly modified or clarified, namely to prohibit sex outside of marriage in its entirety.
while the old law only prohibited sex outside of marriage with non-married couples themselves. like the prohibition of the husband having sex with women other than his wife.
Having sex is a natural human interaction. People meet, start dating, have sex, get married -
this is how it's done everywhere.
Unfortunately, Op is discussing a certain country, maybe where you live the stages are like that but in our country, we get married first and then have sex. So in our country, not everything is generalized like that and cannot be equated with the stages you mentioned. I think everything is clear, I appreciate your concept! For us, a woman needs to be kept pure.