> There are no "killer features" for me there, so I just don't bother.
That is my exact point.
'killer features' for me
with syslog-ng there were a LOT of features that were absolutly killer for people who needed them, but it turns out that the vast majority of people were happy with what they had, and so the pain of having to change how everything currently worked in order to get new features that they didn't care about was enough to prevent just about any distro from switching to syslog-ng as the default syslog
along comes rsyslog, and while it's config files have some 'new, strange' stuff up at the beginning, the main part of the config files looks just like classic syslog, and it's maintained. Within a year, just about every distro switched to using rsyslog as the default, and it didn't bother anyone because their configs either 'just worked' (if they were included), or were dead trivial to adapt.
Now, several years later, there is a significant uptick in the number of people doing things with rsyslog that could never have been done with sysklog (but that could have been done with syslog-ng), in part because the transition was evolutionary, with full support (not just in theory, but in practice by the distros) for using the old style configs.