That’s not true at all. Apple absolutely did despite what Jobs publicly claimed. Users do know what they want, designers know what users want. I wouldn’t ever trust a strict focus on developers that would be a crap experience for anything looking to scale globally. Many Open Source and or free software products/services suffers horribly from UI/UX largely because ids developer focused.
Discussion
You are right on the poor UX/UI of projects made by developers only. That’s actually a great example of the fact that people cannot properly relate to people’s experience and needs outside of their own community.
Doing more user research can help but it won’t fundamentally change that. It’s just a patch on a broken IDE.
The real fix imho is to immerse yourself in the Environment in which the problem occurs. That way, you can either experience the issue directly yourself, or you have repeat interactions with people who do.
There is a massive difference between fixing something for someone that you will never meet again versus fixing something for someone who is part of your community and that you know will still be around next month.
That’s part of game theory. Very different outcome between one time encounters and repeat encounters.
Classic user research creates an artificial environment where there is limited repeat and emotional attachment to the people being interviewed. It’s a hack. It helps but it doesn’t resonate at the same frequency.