[1] http://elementaryos.org/journal/meet-gala-window-manager
[2] (I couldn't find an elementary journal article explicitly about this, but here's one from the Gentoo wiki): http://wiki.gentoo.org/wiki/Pantheon
That's the main point of them making decisions for you. The more opinionated the software, the less decisions the user has to make, the harder it is to mess up the system.
If the data has an open format, then this problem is reduced, but many applications out there have a proprietary data format.
#2 -- Specifically Adobe applications & Excel present big roadblocks from companies rolling over from Windows on OSX. Much of the other software that stopped companies in the past is now web browser based.
#3 -- Definitely an issue.
I've seen many users who have (but shouldn't have) Administrator on their Windows boxes mess them up beyond fixing, usually because of malware.
I am far from a Linux/Unix expert, but I think this has to do with updates and dependencies. Using an Ubuntu LTS release along with not messing with any of the system settings seems to be fairly fool proof. Windows has its share of problems but the only complete failures I have experienced in two decades of use were hardware or malware related.
Never had any issues with the things you mentioned for the last 3 to 4 years.
Linux problems include:
1. Hardware compatibility
2. Office compatibility (also Adobe + games)
3. Easy to mess up your system with no hope of fixing it
I don't see how any of these address the problems with Linux.
I run Gentoo with XFCE as my main OS, SUSE at work, and Windows to make presentations.
Fun things to do include: tight WINE integration, better genkernel, modular configuration structure so that it is harder to mess up and easier to restore.