My point was more, "measurement good; eating psychoactive things off the ground bad."
The "key advancement of chemistry"—the thing that makes chemistry chemistry, rather than alchemy (and as it happens, the thing that differentiates baking from cooking) is being able to measure the reactants we put into a beaker, and clean the product of the reaction of any side-products, such that we can then crystallize/distill/etc. out the product alone, weigh it, and thereby determine the exact potency of product. Once we know that, we can then do all sorts of things: dilute it to a controlled strength; create delivery vehicles that deliver it at particular speeds; put it straight into the body in ways that would just kill you if you put into the body all the other stuff that you isolated the product out of; etc.
Anyone can do this. People make THC tinctures and essential-oils all the time, in their kitchens. It doesn't matter to me whether you do it or someone else does it for you; but it seems irresponsible to me to tell someone to go eat the non-processed version for medical effect.
> Hydroponic cannabis is grown in highly controlled environments and the dosage levels are tested to be within an acceptable range.
Sure, you can control everything about the production of the marijuana itself. But the key to medical treatment is the last mile, and specifically the ability to relate a patient's response over time to a dosing schedule/pharmacodynamic profile for the drug. If you prescribe someone "medical marijuana", without fixing down how they're going to take it, they could very well do anything from eating the whole batch at once, to vaping it every three minutes, to just doing hits off a bong whenever they feel pain. These are not the same thing, and medically they should be different prescriptions if the doctor has any hope of knowing whether the treatment is working.
Pills (or, really, anything more specific than "here's a plant, go to town") let a doctor say something more specific like "take one of these every two hours", and then from there know exactly how much of the active ingredient should be in the patient's bloodstream at any given time of the day, and so be able to measure effects (and side-effects!) against those that are normal, or abnormal, for that level of dose being in the patient's body for that period of time.