Maybe they rushed it out originally, but it's been out for two years now, and I think it's reasonable to expect any rough edges to have been smoothed out over that time!
Speaking as a former MSFTie, my experience is that some orgs (like OSG: Windows) are more conservative with UI/UX changes (between major releases, at least) compared to others (like DevDiv: Visual Studio) and it's motivated by avoiding risk: i.e. "if it ain't broken, don't fix it, even if it is currently uglier than a mid-2000s KDE desktop".