It wasn’t a culture shock but it made something obvious that sometimes gets forgotten. The “Open” just means that one can look at the source code and copy it to make a new version. There is no obligation of the original creators to support things outside of what they want/can do.
FOSS gives people the option to take the original code and create their own version of it in case they don’t like what the original maintainers are doing. With closed source you would be stuck and would have to look for something new.