The Taz 4, 5 and 6 have fully constrained leadscrews, which means there is a top and bottom bearing preventing the leadscrew from flopping around on its own, and more importantly the coupler is not improperly acting as a Z height restraint device like it does on so many other printers. That means you could actually use a different coupler type, and there are theoretically better ones out there.
Aluminum spring couplers such as the Taz uses are fairly stiff, but at an exagerated physics level you can think of them like a slinky. Rapidly turn a slinky at its base, and there will be a slight delay as that motion works its way through the coils and rotates the top to match. In the case of the Taz, that motion is over such a small spring and occurs so quickly its likely not perceptable to the final print at all. A Zero backlash spider coupler on the other hand would theoretically have less of that motion, but again its so small that you probably won’t even notice it. A spider coupling is however more forgiving of motor misallignment to the shaft than a coil coupling, which can reduce issues in printers not running an anti wobble in theory. The tricky part is finding one that will fit the Taz motors and leadscrews that isn’t rediculously tiny and weak looking. I’ll give you a hint in that regard, all of the ones on mcmaster carr that will fit are puny.
Printed ones can work, but in this application the helical coil couplers are likely a superior choice.