For Andrea, this stretch is actually very difficult, first of all because he has ADHD so sitting still for more than 30 seconds is a big challenge for him, but more importantly because if he just relaxes, his legs immediately drop down to the ground so holding them in the air like this is actually a real test of endurance for his inner thigh muscles.
He's grinding this exercise for a new trick he wants to learn where he's hanging in a deep straddle oversplit between two rings from the ceiling (one foot in each ring), and from that position he then pushes himself up just using his leg strentgh to go into a normal split and further until he's "standing" upright in the rings, and then goes back down and back up like a sort of snow angel motion. It's an intense leg workout that Arte came up with for him. For Arte it's a piece of cake of course but a normal human like Andrea (lmao "normal") has to train hard to develop the thigh strength necessary to even attempt that trick.