Most notable: https://old.reddit.com/r/suse/comments/umfyku/the_time_suse_...
Most notable: https://old.reddit.com/r/suse/comments/umfyku/the_time_suse_...
Edit: This guy has some pretty toxic politics, and I wouldn't want him in my workplace.
That being said, it looks like Reddit might be confused about Jewish holidays: SUSECON 2017 appears to have run between Rosh Hashanah and Yom Kippur, like he said. That is indeed a holy week, and scheduling a conference during it is roughly analogous to scheduling a conference between Christmas and New Years'. But I don't think they did that intentionally; it's just unfortunate timing.
(This doesn't mean I buy this guy's story; I don't.)
Like all Jewish holidays, Yom Kippur begins in the evening. In 2017, it began the evening of September 29. Information that I can find on SUSECON 2017 lists it as being September 25-29.
Granted, the last day of a conference almost always ends prior to the evening. However, it is completely unreasonable to require a religious Jewish person to be traveling after a conference on Erev Yom Kippur.
Imagine your employer holding a mandatory conference, in a foreign country, concluding on the afternoon of December 24... and then arguing that it doesn't overlap with Christmas.