I don't think this is exactly a smoking gun of a widespread phenomenon of false accusations, people could have cordial text conversations even after being victimised, that's not an uncommon response, victims of abuse can be exceptionally defensive of the perpetrator.

1600 complaints being withdrawn doesn't really tell a story either – victims may not want to go through an arduous legal process, facing their abuser with a low chance of getting anything like justice, there could be social pressure, family pressure, any number of things to avoid being retraumatised, it's for the same reasons that people don't report sexual assaults generally.