Because users do not know that there's some hypothetical "better" experience they could have had and do not care, unless your service/tool/whatever is not functioning correctly. Prioritizing your employees' enjoyment and experience to deliver more, faster, and consistently, is in all likelihood a better decision than prioritizing some subjective improvement to user experience.
Of course there are exceptions. But it's definitely a hot take to say you should never prioritize DX over UX.
> Because users do not know that there's some hypothetical "better" experience they could have had and do not care, unless your service/tool/whatever is not functioning correctly.
If your business competitors prioritise UX over DX, your users will soon know. And then they won't be your users any more.
This is one of those "false delima" logical fallacies. The idea that you have to choose between a "nicer UI" and "many features, no bugs, shipped promptly".
All those are important, and given a talented team, there is absolutely no reason why you cannot have good UX, lots of features, few bugs shipped on time.
Going back to the original point, "the features they need, shipped promptly, and without bugs" you speak of is actually part of the UX (user experience)!
Maybe you are mixing up the UI design with the UX? In any case, the original point is just highlighting the importance of UX, without giving any solid examples of DX.
Of course there are exceptions. But it's definitely a hot take to say you should never prioritize DX over UX.