A lot of developers feel the need to make their sound as big and impressive as possible on their own, so much that it's practically impossible to integrate them in the context of a piece of music. They exaggerate things a bit.
Those presets are drenched in reverb and chorus and such, and some of them are so over the top that they'll clip your inputs with a single note (hello Cakewalk's Zeta).
Then there's also the other demo factor - in order to demonstrate all that you can do with their synths, developers will often include some extreme settings as exemples. If memory serves me well, Arturia tend to include many of those more extreme presets which pertain more to texture and effects than music. And that's understandable because people use synths for sound design too.
The funny thing is that synths which aren't drenched in effects are often criticized by people for sounding "sterile", yet they work incredibly well in context (Logic's ES-2 is a fine example of that) and can be as impressive as the next guy if you start cheating and adding tons of effect.
I do think that most any of the synths you mention are capable of generating great results.
Personally, I tend to stick to the same set of synths, and since I'm still quite green at programming them, I start w/ presets and work my way up from there. The first things I do is usually to turn off or at the very least cut back on the effects.