I think the answer is fairly simple: 3D content creation suites with all the bells and whistles from A to Z is incredibly complex and expensive to develop and maintain (I’ve heard someone say it’s perhaps the most complex software ever). Divide the high cost of development by a relatively small user-base, and you have high prices per unit. It’s that simple, in my opinion.
Consider that if it were relatively easy and profitable to create 3D DCC suites, we would be seeing a growing number of products appearing, to compete and take some of that money. Instead we’ve seen the exact opposite.
Blender plays a major role in this trend. Having such a capable software available for free in this space has two effects: first, it’s basically slowly killing all the “low-end” competitors. As it becomes more capable, it will increasingly inflict economic damage on competitors higher on the market over time. Second, as users of other software slowly switch to Blender it will reduce the user-base of those other packages, which in turn will make those vendors have to hike their prices even more.
This is now a vicious cycle. 3D software “X” is expensive and has some major weaknesses. More and more users abandon it for Blender and other alternative packages. “X” has to either raise prices, slow down development, or both. Continue this cycle until a few years later “X” is dead. Repeat for “Y” software.
If you seriously consider the overall trend here, I feel that Blender is the only 3D DCC suite that has very good prospects of long-term survival. I think that Lightwave, Modo, and Cinema 4D are on wobbly legs (in order of wobbliest legs first). The next tier is Max, and Maya/Houdini(tie), with Maya and Houdini perhaps being several years out before Blender can compete.
However, there are two factors that limit Blender from destroying more competitors for now: one, the GPL license which prevents tighter integration of commercial plugins. Two, the lack of a contractually-agreed, paid support option for it. I think that those are the main factors that may keep some commercial alternatives viable indefinitely. Both factors could eventually be overcome though, so this is not guaranteed safety for the commercial competitors either.
PS: Does this thread perhaps belong in the general forum instead?