shielding a cartridge Bearing such as the ones Specialized got made for them & sold
are a fine combination ..

the design just didn't get carried over to Freehubs.. the popular Shimano hubs are
loose ball , shielded .. rubber ring around some of the cones..
& road hubs are less drag... by not having contact seals ..

some of the other suppliers (to bike assembly companies) have added hubs with rubber boots,
in wheels fitted to some modestly priced bikes, I note*.. the boot weather seals quite well ..

* assembling them for sale in LBS..

My Rohloff hub uses lots of cartridge needle and ball bearings inside, none have seals,
just an external oil seal to keep the oil inside, wetting the parts.