Re: Baby steps
MS Office has historically a hard time understanding files formatted in different versions of MS Office. The only format that seems consistently understood is when you use o365 and read it on o365.
This is of course the exact scenario anyone concerned at all with data sovereignty wants to get away from - it requires a cloud, and a cloud controlled by a foreign government who have a very different concept of privacy to you (and, let's be honest, different to what we as citizens actually think of when we use the term Privacy)
LireOffice actually handles Track Changes pretty consistently, as does Google Docs. The only time it falls over is when someone *imports* the shared circulated document into a desktop version of Word - often because the company has a security policy which is "don't ever trust microsoft word to open an external microsoft word document" - and then everything gets anonymised and simple formatting gets borked. Problems I *never* have with companies using non-desktop Word, by the way.
We can always find reasons why not but itn the end it usually boils down to "because I don't want to change". The world can handle more than "the way we did things in 1990" now.