while well documented, are needlessly complicated and only really viable in Azure for the most part. They are also very good at not exposing the underlying tech to managers, preferring use of buzzwords.

Yeah exactly because managers don't care about tech, its all about hype and buzzwords. Microsoft has other reasons to keep their tech as it is probably something around of way I described in here.

Either way the truth is that the alternatives, less say, LibreOffice/OnlyOffice and NextCloud aren't really alternatives for most use cases. NextCloud is a shame, they should be ashamed of calling themselves an alternative to Office365 / Teams / OneDrive. They're pretty much like Tesla, if they didn't spend most of their time over-promising + under-delivering people would be surprised with the progress they've done instead of going for scrutiny.