Gobert does not have skinny legs. For his body type his legs are huge.Look how skinny Rudy's legs are at 23 seconds in this video. He's been skipping leg days. His landings on some of his dunks look like you'd think they'd look with those skinny legs. He is super fit though. He just needs about 15 more pounds...
https://www.nba.com/jazz/video/teams/jazz/2018/07/25/2193810/1532540150546-rudycampmisc-2193810