Medicine is hard. Unlike, say, physics, you cannot experiment on people except in very specific circumstances. Rats, mice, chimps etc. aren't people, so researchers work on "animal models", but in many cases you're just giving lab rats an Alzheimer-like disease and curing them of an Alzheimer-like disease, which is nothing like curing actual Alzheimer in actual humans. (Yes, animal models often involve inducing a "fake" disease in animals — testing treatments for psoriasis involve giving imiquimod to genetically modified rats, for example. This activates some of the same immune pathways, but it ain't psoriasis.) Alzheimer is particularly hard because we can't really study what's going on in the brain while people are alive, and when they're dead and can be dissected, we can only see the remnants of that activity.
If science has been hyped up too much, I think we have the media to blame, not scientists. Media turns very early, pre-clinical, merely promising research into headlines like "Could This Promising New Discovery Be a Cure For X?" Meanwhile, tons of progress is being made; you probably just don't notice it. Monoclonal antibodies (like Humira) for autoimmune disorders like Crohn's, ulcerative colitis, arthritis, psoriasis, etc. have been complete game changers for people with autoimmune illnesses that involve the overexpression of certain cytokines like TNF. Same with JAK inhibitors and PDE4 inhibitors. There are tons of things with good treatments now, but you probably don't hear about them because it's not that sexy and therefore not covered by media. As for cancer, it's not a single, monolithic disease, but a whole lot of different ones (melanoma, lymphoma, leukemia etc. all have different causes). Huge leaps have been made with some (like melanoma), and for many cancers a lot more people are surviving than the 1950s when chemotherapy was in its infancy (methotrexate, the first chemo agent, was discovered in the late 40s) and most attempts to treat cancer involved surgery.
If science has been hyped up too much, I think we have the media to blame, not scientists. Media turns very early, pre-clinical, merely promising research into headlines like "Could This Promising New Discovery Be a Cure For X?" Meanwhile, tons of progress is being made; you probably just don't notice it. Monoclonal antibodies (like Humira) for autoimmune disorders like Crohn's, ulcerative colitis, arthritis, psoriasis, etc. have been complete game changers for people with autoimmune illnesses that involve the overexpression of certain cytokines like TNF. Same with JAK inhibitors and PDE4 inhibitors. There are tons of things with good treatments now, but you probably don't hear about them because it's not that sexy and therefore not covered by media. As for cancer, it's not a single, monolithic disease, but a whole lot of different ones (melanoma, lymphoma, leukemia etc. all have different causes). Huge leaps have been made with some (like melanoma), and for many cancers a lot more people are surviving than the 1950s when chemotherapy was in its infancy (methotrexate, the first chemo agent, was discovered in the late 40s) and most attempts to treat cancer involved surgery.