Well, actually quite a lot of programs had trouble with OS 10.4 when it came out.
A quick check reveals one of the compatibility lists that still remains up:
http://www.macintouch.com/tigerreview/incompatibility.html
And, at the time, I was quite active in Apple's Discussion group, and found that I was constantly helping others with programs that no-longer worked for them. Usually, their only choice was to purchase a new version, or go back to OS 10.3.
It's quite honestly not worth my time to comb back through the archives to locate all those old discussions.
........
In the end, the degree to which compatibility affects you will be determined by which specific programs you use. If you happen to use programs that offered free updates, then you'll be less affected. If you use programs who's authors decided it was a good excuse to charge for an update, then you'll be affected more significantly.
I agree with your statement that it depends on what you use (and the quality of the vendor taking Symantec and Dantz as examples of bad vendors IMO) but going through that list I see a few trends -
1) I would say 30-50% of those listed are either not related to 10.4 (Acrobat being quicktime 7 on either version of OS, or X11 which I use extensively and almost all of the problems were due to not reading the release notes) or just user error reported as related to the last change to their system. A good example of these is the Word and Excel reports for which I'm still using the un-upgraded 2004 on 10.4.8.
2) The list doesn't really represent a lot of issues overall, percentage wise, and are primarily related to system level stuff like printer drivers and disk-drive tools (which I've never needed despite maintaining about 30 users who have no idea what they're doing )
3) a number of issues reported were 'fixed' by re-installing. This points to Apple's need to do a better job of the upgrade process, not breaking compatibility.
So I still think you're original post is over the top in how it was presented despite that fact that, of course, the upgrade is not perfectly compatible.