In my experience that is no longer the case for most distributions. Certainly Debian Stable and enterprise distributions can be fully upgraded without problems. Even Ubuntu does full upgrades by default when software is out of date, and I've never seen that break anything. For that matter, I've never seen a full upgrade (i.e. slackpkg upgrade-all) break anything on Slackware.
(And just as well too, given the enormous number of vulnerabilities that can build up on a typical Linux desktop install.)
The only distro I know of (other than Vector) that advises against full upgrades most of the time is aptosid, and that's because it's based on Debian Sid, so the repos can be full of broken stuff at any given time.
I'll grant you that avoiding full upgrades is a good way to have a stable system, but it's not a good way to have a secure system IMO. Whether one finds it suitable basically depends on whether one values stability or security more; and when push comes to shove, I value security more.