In this question there is an answer that comments "There was for a long time resistance in some parts of the Linux world to Esperanto, so it seems it was only this year that the Esperanto localization was made official in the libc, the basic library in Linux, although some distributions such as Debian and Ubuntu had Esperanto for a long time." What level of resistance was there, and how has it been resolved?
Well the resistance is/was similar as resistance to Esperanto in any other segment of society. In this case, see for example https://sourceware.org/bugzilla/show_bug.cgi?id=711#c2 or https://sourceware.org/bugzilla/show_bug.cgi?id=14943 for some of the history. This particular issue has been fixed: https://sourceware.org/bugzilla/show_bug.cgi?id=16190. With libc now (since only this august) including eo locale in the distribution, the main sticking point in terms of basic out of the box language support is resolved. The problem with libc was the fact that the maintainers were actively opposed to including Esperanto locale, refusing to even consider changes done by other people for inclusion.
Though note that Debian, and hence Ubuntu, included EO support for quite a while now.
I remember long time ago (15 years) when I first considered learning Esperanto and I was working on GNOME at the time, I did hear some disparaging comments about EO. Linux was, and especially the companies around Linux were, trying to be professional, and EO was not perceived that way.
Although I have been mostly out of the active free software community for a while, so I am not sure what is the prevailing view nowadays. But note that the free software community is a very wide ranging far flung community with people of all sorts of different views. It is not a homogeneous bunch at all. But a lot of the core people around Linux and related projects work for Linux companies rather than being volunteers, and this does change the way a purely grassroots movement such as Esperanto is going to be received.