But that ship sailed, the good of the downstream users' contributions are not enough to cancel out the negative net value of the builders' bad behavior.
I absolutely haven't said I consider builders bad and I also was careful not to say rebuilders! I am being very careful with my words. Please don't put things I didn't say in my mouth.
However: unfortunately part of what you said is true. Red Hat apparently took this decision because of some new facts that caused the negative from the "rebuilders" to increase, and the decision had the potential of hurting the users of the rebuilds.
Fortunately it's clear now that there are multiple ways for the downstreams to adapt[1]. Users will be able to keep their distros and—if they wish—contribute in a number of ways to the community. And builders and Red Hat will be able to collaborate in a shared place which is ELN for major released and Stream for minor releases. In a sense this removes excuses from Red Hat and should make everyone feel safer.
[1] you could say despite Red Hat's change, and I accept that. But it's also thanks to Red Hat going overall beyond the requirements of the open source licenses, with things such as Stream and the UBI source container.
But that ship sailed, the good of the downstream users' contributions are not enough to cancel out the negative net value of the builders' bad behavior.