[mrweasel]

The complaint that OOXML was overly complex was a criticism when Microsoft first introduced the format, but as you point out, it needed to be able to handle decades of old formatting rules back then already. While I'm sure that there are stuff in the format that Microsoft made needlessly complex, one has to remember that they still need to be able to maintain the code, so throwing in to many roadblocks for open source developers would likely come back to haunt them. Still we know they did just that with SMB, so why not with OOXML.

What surprises me is how well LibreOffice handles various file formats, not just OOXML. In some cases LibreOffice has the absolute best support for abandoned file formats. I'm not the one maintaining them, so it's easy enough for me to say "See, you managed just fine". It much be especially frustrating when you have the OpenDocument format, which does effectively the same thing, only simpler.

[grahameb]

A friend had a book she'd written in a Mac version of word from the early 90s; none of the current Microsoft versions of Word (windows, mac, web) would read it, but Libreoffice worked fine, so a little script later using Libreoffice's CLI tools and it was all converted, pretty much intact.