Those are all drugs of abuse, whereas Welbutrin somewhat mimics them partially, which is why it shares some of the tolerance and withdrawal effects. No one is denying that drugs work by altering neurochemistry. But is this really desireable to you?
The reason cocaine works is because it short-circuits the nucleus accumbens. This can actually happen from blocking DAT only (DAT removes dopamine from synaptic cleft) but the drug also acts directly in this area. This gives you the false feeling of having accomplished something good, when in fact you did not. The fact that the brain works with dopamine, like a computer works with electricity, doesn't really reflect on how both things relate to each other to produce complex behavior, nor how that would be beneficial to our lives.
Your brain chemistry is in a disregulated state if you take psychotropic drugs. Over time it performs several adaptation mechanisms to cancel the anomalous effect, but you will still be left with various ill side-effects because those adaptation mechanisms are initially very makeshift and can never perfectly undo the imbalances that the drug produces. For example you will very quickly fry your reward circuitry with cocaine, making everything you experience but taking the drug feel a lot less worthy to pursue, and the stimulating effects from increased catecholamines will also quickly fade. But you will be left with the ill cardiovascular side-effects for example and also be more prone to pursue risk-taking behavior, gambling and sex addiction, due to the drug acting on different subtypes of the receptor and in different brain areas which creates more fine-grained imbalances that are harder to cancel.
So no, nobody is denying that "heat" exists in your arteries. There is plenty of evidence for that, like people having fevers which are dangerous. Also no one is denying that slitting your wrist will remove heat from your system according to the laws of thermodynamics. However it is a non sequitur to think that it is desirable in order to improve everything you might associate with "decreasing heat", like being too aggressive to your wife, feeling on the edge at work or having frequent headaches. The same way people nowadays associate all sorts of things with dopamine, like happiness, love, sex or energy, that are in fact totally untrue to how the brain functions in a normal state.
I hope you understand.