I think it's silly to label one ski and one snowboard though. You're out on the mountain in snow, sliding down...how different does this stuff have to be?
Real different. This goes back to the 90's, when snowboarders were considered "counterculture," and most ski wear makers weren't real interested in their specific needs. As a result, a lot of new companies emerged, some to great success, and provided redesigned outerwear from head to toe.
Prime example: pants. Ski pants just don't cut it for boarders. They surely didn't in the 90's. They were too closely cut, with insufficient insulation on the "backside," which is sat upon far more often by boarders than skiers -- after every lift ride, in fact, except perhaps by the pros who can strap in while sliding. Standing upright, strapped in and motionless on a board is not as easy as on 2 skis.
I remember when ski pants had few if any usable pockets. Cargo pockets were snowboard outerwear innovations. (Most riders carry binding adjustment tools to change their board stance.) So was zip ventilation on pants. Ski pants fit differently over snowboard boots. Another design modification happened.
So, for the riders, these changes and modifications were beyond welcome. And, as a result, brand loyalty was established, via reputation. Take one look at the ads in any snowboard magazine, and you'll see brands that many skiers have never heard of. But brands like Orage have crossed over. As has R.E.D., still one of the lightest and most durable helmets out there, but not hugely ventilated (and for a reason).