For me, I've often wanted to shoot with flash at 1/500th or so outdoors, but most mirrorless cameras only go up to like 1/160th. Back in the DSLR days, there were a few camera bodies that would go up to 1/500th. Its insane to see flash sync beyond 1/1000.
Note that a full power strobe will burn about 1-1.5 ms, so below 1/1000 you start to loose the ability to balance flash versus ambient via shutter speed.
