Yes, the synthetics need a different technique from boar or badger when you load them and lather with them to avoid that issue. I had that issue too when I first started to use synthetics until I figured out how to avoid that. I face lather and the brush sits upright on the counter while I shave and rarely have that problem unless I tried to put too much water into the brush. Synthetics are not badgers, likely never will be, and need to be treated differently is all. The again boar or horse hair will never be badger either but nobody expects them to be for some reason.
Bob