It has improved since the dark ages, but it’s still the same approach. Trial and error. And we still treat many illnesses by poisioning the body and hoping we kill the disease before the patient (chemotherapy, and actually antibiotics), just like leeches. And most treatments aren’t even specifically delivered to the site of the issue. We swallow them and let themspread everywhere. So we have to take way more to get the concentration we need where we need it. You need look no further than at the abysmal suscess rate of stage 3 trials to see that they have no idea what a medication will do to most of the body. We can split the atom, walk on the moon, and annilate every human on the planet. But we can’t even reliably cure a headache, or even stop pain. We can dull your mind so you don’t care about the pain with addictive substances that have lots of side effects, or we can knock you out (and only most of the time wake you up). We need more understanding. We need better diagnostic tooling. We don’t even have a non-invasive way to reliably tell if an illness is viral or bacterial for a reasonable enough price to use it often.