We had access to porn on VHS and for us nerds via BBSes/dialup, if anything that just increased the drive to find the real thing. You don't lose interest in eating your dinner just because you saw pictures of it on the menu when ordering. Especially when it's still all totally new experiences and hormones are raging.
But what was also true in the 90s was men still largely controlled access to resources. That alone puts significant pressure on women to subject themselves to men, just to have people to drive them around and take them out to dinner or on vacations, or pay the rent in a first apartment. Combine that with a seemingly total ignorance of facts like practically all cervical cancers are caused by HPV, and casual sex can easily be common.
Today it's very different. Just the other day I read an article about GEICO being sued for their insured negligently giving a woman HPV during car sex [0]. I have the impression that women are simply better educated and have better options today, and that's A Good Thing.
Having said that though, the last time I tried online dating, which was before it all pivoted to mobile, the few dates I went on were very obviously women seeking free dinners. So at least within my age group, things seemed to still be more of the same in that regard.
[0] https://www.npr.org/2022/06/10/1104134521/geico-lawsuit-std-...