I was curious, and I did a search for "deleted:1 user:me" to see if any of my posts had been deleted, and six had, almost all of them I had deleted myself. For context I have posted around 200 posts on Stack Overflow.
Being able to see deleted posts is indeed an eye-opener, and I also wish more people had this ability, but for a different reason. It makes you aware of the amount of very low quality posts that get posted to Stack Overflow, not to mention spam.