I understand the point you are making, but in reality drugs will get developed based on their likely risk/reward ratio only.
If you want more diversity, unless there is a non-market force (which honestly shouldn't be needed here, there is high demand), pharma companies will just keep picking at the lowest hanging fruit.
Eventually, they'll get up to the non-stimulant variety, but developing an entirely new class of drugs is a Herculean effort with very low likelihood of payoff. To make it work, you need more data on the disease (e.g. more time), and some luck out of academia (which is where 99% of drugs come from anyway). They will also need a lot of money to do it, so anything they can produce in the meantime is essentially on that track. Thus, the wording "even more drugs".
If you want more diversity, unless there is a non-market force (which honestly shouldn't be needed here, there is high demand), pharma companies will just keep picking at the lowest hanging fruit.
Eventually, they'll get up to the non-stimulant variety, but developing an entirely new class of drugs is a Herculean effort with very low likelihood of payoff. To make it work, you need more data on the disease (e.g. more time), and some luck out of academia (which is where 99% of drugs come from anyway). They will also need a lot of money to do it, so anything they can produce in the meantime is essentially on that track. Thus, the wording "even more drugs".