If the only purpose of licensing were to generate new taxes then it should be opposed. But there appears to be other good reasons for licensing for licensing software professionals. The absence of maturity is a strange standard. The science of software development is not yet a complete or static body of knowledge. This should not exonerate a software practitioner from following those testing and design principles that are already known.
Some objections claim that licensing is no guarantee of applied competence.
This is correct, but it focuses on the wrong side of the question. The absence of licensing means that we have no way of knowing whether the developer has any knowledge of the current best practices. Licensing will only provide assurances that the developer knows the best practice and as stated above there are other pressures to encourage them to follow these practices. At this time there is no counter-pressures to resist the development of shoddy software justified by budget and schedule pressures. The introduction of licensing would introduce significant counter-pressures.