I would add that the market seems like it settles out with companies releasing either for free within a larger release, such as the bundled effects and synths in the various recording software packages available - Sonar, Cubase, FL Studio, etc., and also with both free and commercial software that is available - that runs on multiple recording software platforms.
I think it basically works itself out over time, due to market forces. Certainly not in all cases, but in lots of them.
Further, though there are indeed differing collections of included effects and synths with various recording software offerings, if you understand how to configure a delay, or a reverb, or whatever, then there is not really an obstacle when presented with the various different interfaces from these different collections.
Of course, the above is a simple characterization of my own viewpoint on the matter, and may differ vastly with anyone else's.
Bob Bone