There are many arguments I've heard about price discrimination being annoying, but deadweight loss is not one of them. Quite the opposite, fixed prices in the presence of undeserved pricing power results in a less than socially optimal amount of production, and price discrimination tends to reduce that.

To say nothing of the implicit argument that software service providers have undeserved pricing power; I think that's begging the question, but it's not really relevant to my quibble here.