This ties in with his 'delusional arrogance' but it was pure stupidity on his part to be a public figure and send out text/emails in the clear like that. If he had used an email encryption service, the content would have been only seen by his intended recipients, coudn't be forwarded, and the messages would automatically self destruct after a period of time. There are free encrytion services that are very quick and easy to use. He was arrogant and careless. I use this free service to send and receive encrypted emails at
https://www.sendinc.com/