For making a good GUI, the tech guys need to be ordered around by non-tech guys who think like, or talk to, regular users and know what is needed. Tech guys don't like this, so someone needs to pay for their suffering.

I suspect Dijkstra made the relevant distinction in a different context: the open source process is geared to providing correct software, not pleasant software.

> The pleasantness problem deals with the question how satisfactory a system meeting a given functional specification would be; the correctness problem deals with the question whether a given system meets that functional specification. The correctness problem being an entirely technical one, the functional specification can provide strong heuristic guidance for the system designer.

You have clearly not see the user interface of most (as opposed to the most popular) pieces of closed-source software.

That's not really a rebuttal though. 90% of all UX can be bad, but it's still notable if 99% of OSS UX is bad.

Actually needing to sell your product eventually/get people to use it seems to be a fairly necessary part of ending up with a good UX.