Likely there would be more evidence. Eye witness accounts of the two parties together around the time of the incident; photos taken before or after the assault; Hospital records; Police reports made that were not followed up at the time; Texts; Call logs; surveillance video. There is a lot of evidence that can support an accusation like this.
As to why it’s been so long, coming forward after events like this can be terrifying. People who have been assaulted can hold a lot of self-blame. They can feel alone in their trauma, and the chorus of “she was asking for it” and other bs would be a big deterrent from coming forward. Isolation and stigma are a big reason that powerful people have gotten away with being abusive monsters for so long. It’s also why multiple accusations seem to crop up at the same time. The claimants see others who have suffered like them and feel less isolated and more supported in their claims.
Likely there would be more evidence. Eye witness accounts of the two parties together around the time of the incident; photos taken before or after the assault; Hospital records; Police reports made that were not followed up at the time; Texts; Call logs; surveillance video. There is a lot of evidence that can support an accusation like this.
As to why it’s been so long, coming forward after events like this can be terrifying. People who have been assaulted can hold a lot of self-blame. They can feel alone in their trauma, and the chorus of “she was asking for it” and other bs would be a big deterrent from coming forward. Isolation and stigma are a big reason that powerful people have gotten away with being abusive monsters for so long. It’s also why multiple accusations seem to crop up at the same time. The claimants see others who have suffered like them and feel less isolated and more supported in their claims.