Yeah that's also why I stopped using it. Why didn't they just fork it and change the name? I don't get it.
FWIW at some point it also had quite severe stability issues. I'm sure those were solved but that might have contributed to the fact why there was no effort to fork it but instead people went with ZFS, XFS and eventually ext4
There is no need to over-analyze this. It's perfectly legitimate to feel that it's weird to use an FS created by someone who murdered his wife, or otherwise violated or opposed norms that you hold important. For instance, I certainly wouldn't use something called HitlerOS as my daily driver (or at all), no matter how good it was, because the name itself makes me uncomfortable.
Then i should not use a linux system because it contains code from NSA, Google, Facebook, Apple or even Microsoft. That's not a reason not to use a system. The US was more than happy to use things created by german war criminals ( V2).
If you care about those things very deeply, then perhaps that is exactly the right thing to do. Lots of people don't do things because of ideological or personal beliefs, even if it limits their options.
Many people use the BSDs for their transparency and despite Linux catching up in many areas, BSDs (which are arguably more political) have a rock solid reputation. (Maybe that's why all of Apple's flagship products are based on BSD - never heard of them using Linux though) IMHO people forget that software development is of course about the tech but really half of the work is about people, both in Opensource and Commercial developments. Large orgs think twice before they use a (perhaps free) software with bad reputation
There's no need to overreact about it either; no need to judge the book by its cover. To use your example, some people are having allergic reactions to the software as if it were named HitlerFS. The conflation is exaggerated. Dismissing great software because it was named after a man who would years later murder someone won't bring the victim back. It just eaves the world with less great software. Pointless and misguided moralism.
As I pointed out, this is not moralism. Humans aren't cold, calculating logic machines. We have emotions, and we care about our social standing.
If I choose to use a slightly inferor alternative because the name makes me uncomfortable, that is perfectly legitimate.
If using ReiserFS costs me a number of weirdness tokens (like using it in a workplace, and the relevant decision makers are likely to know about the murder now or in the future), then I may choose not to use it to conserve those tokens for other controversial initiatives that I care about even more.
Neither of those decisions may be "rational", but it's also not moralising. I simply have to take a complicated social/emotional calculus into account, something that most do unconsciously 24/7 without thinking "hmm, today I shall get on my moral high horse and decide that this is moral and the other thing isn't".
FWIW at some point it also had quite severe stability issues. I'm sure those were solved but that might have contributed to the fact why there was no effort to fork it but instead people went with ZFS, XFS and eventually ext4