"The PD is a science fictional projection of the naturalistic fallacy and injunctions against playing God. It’s also a disturbing application of social Darwinism. The underlying assumption of the PD is that a civilization must attain space faring capabilities and advanced technologies through their own means (civilizational uplift is not an option, I suppose). It’s survival of the fittest as decreed by the Federation, and those who cannot progress to an advanced developmental stage or who destroy themselves first simply didn’t deserve to be in the Federation in the first place."
This is a fascinating perspective that deserves due consideration, but I find it problematic for a couple of reasons. The first is that the Prime Directive is intended to curtail the Imperial arrogance that has tended to characterize Western technoculture's interaction with "primitive" cultures. The approach that Dvorsky suggests -- "uplifting" the pre-warp civilization -- is itself open to the criticism that it reiterates the ethnocentric hubris of past ages by perpetuating the notion of "The White Man's Burden."
A further objection to Dvorsky's perspective is the recognition of the unintended consequences that can result from such interactions. A vivid example is provided by the Cargo Cult phenomena which illustrates the distorting effect an advanced technological culture can have on a tribal society. A science fictional dramatization of similar unintentional disruption of native society by spacefarers can be found in H. Beam Piper's short story "Naudsonce."
So while Star Trek's Prime Directive remains a problematic concept, and Dvorsky's analysis provides a stimulating critique, it is my opinion that his objections don't entirely discredit the concept.