Yeah, but a jetstream at that altitude might have slowed his jet to a standstill.
I would rather it be a UFO, though.
Gulfstream V cruises at Mach 0.8 at 41,000 ft. That’s a heckuva jetstream if it can cause a jet speed across the ground to stand still.
A British Airways 747 once set a record for a NY to London flight when it clocked a ground speed of 825 mph. That’s close to a 300 mph tailwind (jetstream). Still not enough to “stop” a corporate jet going the other way. It would get the pilot’s attention, I’m sure.