There are more sinister ways to force people to do something than just outright requiring. People seem to have forgotten, or never knew, that time when new DirectX was supported only on Win7 and didn't work on previous versions mysteriously, but all new games required it. WIndows 7 didn't see such a huge adoption naturally. Same thing when new Office is released file format changes just enough so that old Office doesn't support new files, but new Office supports all the formats, so people would end up upgrading. Otherwise majority of people don't need more than configuring margins, fond sizes and bold.