It takes only a small amount of risk to make an activity a bad choice. If 5% of people who walk through a neighborhood are mugged, anyone with a choice will avoid walking in that neighborhood, even though an overwhelming majority of 95% would be fine.
The calculation around dating is similar. If there is a 3% chance going somewhere private with a guy would result in nonconsensual sexual activity, it's not worth doing. Not fair for the 97% or whatever of guys who have normal behavior boundaries, but life isn't fair.