While you are taking the idea to the extreme to make a point, I agree with the underlying argument that we should work to modify behavior to improve outcomes.
A lot of money has been spent reducing tobacco use which has paid for itself in better health outcomes.
When there are multiple cost-effective public health measures that can achieve the same end, we should pursue all of them.
In the case of Truvada, we already did the hard part (inventing it). Now it’s just a chemical that can be infinitely duplicated a low cost. It would be a huge wasted opportunity, a moral crime really, not to give it away for free to everyone that can benefit from it.
And the same is true for the flu vaccine, the birth control pill, the seat belt, etc. These are miraculous technological advances. If you support the use of these advances, but not Truvada, I would take a hard look at what factors might be playing into that.
A lot of money has been spent reducing tobacco use which has paid for itself in better health outcomes.