What exactly does "spend time" mean in this context? Just chatting and having a drink together?
Edit: In the billionaire league you can hire an entire small corporation to look after your interests. Lawyers, PR people, "influencers", security experts - whole offices of full-time employees and contract hires who do nothing but You.
If you're any good at it, you hire people who can hire people who can hire people to get things done covertly by back channels - if necessary.
So getting associated with someone like Epstein certainly is a huge mistake. And not just a personal one. Either Gates knew the risks and personally decided they were manageable, or someone decided that Gates needed some bad advice.
Considering that Gates is now divorced, I suspect the former. But at this distance - who can tell for sure?