Well I think the root of the problem is more complicated.   People don't buy dynamic clothes for various reasons:  they can't be bothered, they'd like to but end up frustrated and they're not impressed.  

In the first case it seems more complicated to them  to run simulations especially if there are several and the different clothing items have to interact with each other and scene props as well.   I've wasted some time going back and forth and constraining or changing settings until I could get everything right on 2-3 items only to have Poser crash on me (I'm talking about older versions not Poser Pro 2012 - but not everyone has that).

Secondly, we've all seen the tutorials where we apply the clothing, move slider, apply pose, and run simulation.   Fine but what about tutorials where the figure is interacting with the clothing, lifting it up or having it drape on steps, etc.   There are no tutorials out there for such details except for one I found on SM's site which wraps the clothing around the figure.  Dynamic clothing's biggest selling point would be all this but it's not easy to do without seeing some examples.    I felt so stupid after I saw a tip PhilC gave to someone about getting a desired shape by using helper props.   I don't think that's intuitive at all and more tutorials dealing with these aspects of dynamics would do a lot to drum up interest.

And finally a lot of the dynamic clothes out there are simply not that great.   I think many people find it much easier to model instead of rig for perfect conforming fits so a lot of the freebie stuff is by people just starting out modelling so the clothing itself is plain, usually looks unrealistically thin with no real modeled details such as buttons, seams, etc.   Also, I can't recall seeing many dynamic clothes  that come with as detailed textures as most conforming ones have.   At best they are simple fills and usually the mapping is also not helpful in texturing them.   Again, I would attribute this to the inexperience of the modeller at uvmapping.

I'm not in any way saying that all this applies to ALL dynamic clothes out there.  There are beautiful examples of detailed clothes with great textures but there is also a lot of "tube" mini dresses that anyone could do with a primitive and shrink to fit right within Poser.   There was discussion about these very points a long time ago and hope that slowly modelers would pay more attention to dynamic clothing and not see it as an easy 30-min. job but I'd say we still have a long way to go. 

I'd like to see dynamic clothes where the modeler has already set constrained, soft decorated, rigid decorated, etc groups to act accordingly and maybe gives at least the settings for resistance, friction, density, etc that would be best for that item.  

Hybrid clothes would be great too.   Steve at Poserworld has done this on many occassions and the results are amazing.   I used a conforming dress of his and just ran the simulation for the hip part of the dress to get a good sitting pose. http://www.renderosity.com/mod/gallery/index.php?image_id=2101767&user_id=2482&np&np  I did the same thing here as it was much easier to make the hip dynamic than fiddle with the various posing handles and still not come up with a good sitting pose.  http://www.renderosity.com/mod/gallery/index.php?image_id=2187422&user_id=2482&page=2&member&np

I believe some special preparation is needed for hybrid clothing and not all conformers can do this successfully but I fiddle around and see what works and what doesn't.  Not many users would like to do this so it should already be set up for them in a working fashion.

Some more tutorials on how to best pose a dynamic item with your character sitting, lying down, etc might be helpful too instead of just a simple standing pose.  

I love working with dynamic clothing so I'd definitely like to see it reach its full potential.  And if you've read this far, thank you :)