MS have claimed numerous patents which they will STILL not disclose. FAT32 is only a known factor because it is also an issue with cameras, audio players and such.
At the end of the day, if I decide to install Windows on a system bearing Linux, then that Linux system is in peril. If a user receives a Linux ext3-formatted SD card and puts it into a running Windows system, the user will be told the card is unusable until it is formatted.
Where office formats and disk formats are concerned, MS still only has two modes: Pretend its noise that should be erased, or freakout send a SWAT team of marketing psychologists and lobbyists to get you to switch back.
Its nice that MS makes FOSS-friendly noises in the server/cloud space. That is what bullies do when they get their asses kicked. If MS gets the upper hand and their vendor lock-in starts working here, then the friendliness WILL evaporate.