Jealousy is not quite the word to describe precisely how I feel about those with foreskin. I admire foreskins very much and , having been cut in mid life , I know what one feels like and what one can do to enhance a cock's appearance and function. I also know the disadvantages of a foreskin.
Overall , I feel the benefits outweigh the disadvantages of having foreskin and so I have been regrowing mine for 7 years. I will continue to regrow as long as my lifetime permits me to do so or until my new skin feels just about right!