Good negotiator would need leverage and in most cases that won’t exist for a product that understands its own value well. These are priced on value, the call us definitely lowers the noise but it has more to do with the target demo being enterprise large customer deals. Not providing pricing gives sales the ability to try to price it for value to capture maximum margin.
It is most definitely about the products sales team sizing up the potential client and how much they can get the client to pay, based on the company size and turn over. It's possible for the client to negotiate, but the product sales team have jack up the price way over their internal list price, so any client savings is only a fallacy