This is a bit in the same direction as Epstein’s horrible tech higiene- using computers with outdated software, little or no cryptography, and so on. Another person summarised it quite well: “too rich to care”.

Maybe he considered himself beyond prosecution. So he didn't care that he arranged trafficking on Gmail under his real name.

Additionally, if Gmail is a problem, Sergey Brin went to his events.

In one document drop Joi Ito is asking him about security hygiene and saying he is "worried about his emails".