Agreed. All other improvements LO makes are futile until compatibility is 100%.
LO works very well in a closed environment with only LO users, but it doesn't work to share documents with Office users.
MSO works very well in a closed environment with only MSO users, but it doesn't work to share documents with Office users.
That is because LO actively uses a standardized and well documented document format while MSO created it's own that has dependencies that only MSO resolves.
It will never get there. Not just because the OOXML spec is a behemoth but because MS has every incentive to not let it get there. They have the most popular document format in the world which is open enough to avoid legal trouble but unwieldy enough to ensure that people have to buy MS if they want to use it.
That is because LO actively uses a standardized and well documented document format while MSO created it's own that has dependencies that only MSO resolves.