German speaking countries went through an effort to reduce the most obvious spelling exceptions in 1996. It introduced new spelling for many existing words but also allowed the use of the previous spelling to continue (in effect creating the situation OP describes where different options are equally valid). I lived in Germany at the time and remember a lot of resistance and confusion after the changes went through. Also, some of the leading newspapers defined their own in-house rules (based on valid interpretation of the official rules).

https://en.m.wikipedia.org/wiki/German_orthography_reform_of...