You're looking at the side effect of the entanglement that using Microsoft products brings along to ensure later migration will be too costly.
It's a mix of interdependencies, absence of open standards and any anti-competitive measure they can get away with. Add to that their wining and dining of government officials, law makers and high end people in companies who have no clue but do have budgetary and decision power, some law breaking and IP theft and you have a Hotel California model that has been in play for some four decades now.
That's why it's always better to start a company on open principles, as converting later is possible but your motivation will then not be cost because the untangling prior to conversion will burn a lot of money to. The best arguments for later conversion are massive risk reduction, better resilience and higher productivity. And pragmatically, freedom doesn't count - it's a nice factor, but it's hard to translate to tangible numbers on a spreadsheet.