> For starters, it still had a closed, binary (read: not friendly to source control) format
Word still has a closed format. It supposedly standardized OOXML, but - it doesn't follow that standard; Microsoft apparently managed to warp the XML standard to accommodate its weirdness; and all sorts of details encoded by MSO in that format are not actually documented.
There also used to be the problem of different renderings on different machines (even if you had all the relevant fonts installed): You opened a document on another person's computer and things were out-of-place, styling and spacing a bit different, page transitions not at same point etc. I don't know if that's the case today.
Granted, though, hangs and crashes and weird gibberish on opening a document are rare today.
> You opened a document on another person's computer and things were out-of-place, styling and spacing a bit different, page transitions not at same point etc.
When this happened to me on my job in the late 90s we were able to locate that problem in the printer driver that was visible in the Word print dialog. I don't remember the details but it looked like Word was adjusting font metrics to the metrics of the specific printer, and all the shifted pixels quickly added up to destroy the finely balanced lines of our print publication (yes, an official public health periodical by a European government was typeset with MS Word, and there was a lot of manual typographical work in each print). Given the technology at the time, it's not clear to me whether Word's behavior was a feature (in the sense of: automatically adjusts to your output device for best results) or a bug (automatically destroys your work without asking or telling you when not in its accustomed environment).
> Given the technology at the time, it's not clear to me whether Word's behavior was a feature or a bug
A bug, because even if this was merited somehow, they could have just made it a nice prominent checkbox for the user to decide what behavior they wanted.
Word still has a closed format. It supposedly standardized OOXML, but - it doesn't follow that standard; Microsoft apparently managed to warp the XML standard to accommodate its weirdness; and all sorts of details encoded by MSO in that format are not actually documented.
There also used to be the problem of different renderings on different machines (even if you had all the relevant fonts installed): You opened a document on another person's computer and things were out-of-place, styling and spacing a bit different, page transitions not at same point etc. I don't know if that's the case today.
Granted, though, hangs and crashes and weird gibberish on opening a document are rare today.