How do the outcomes compare to people with ADHD who were unmedicated? It's possible that the medicated outcomes are poor and yet still better than the unmedicated outcomes.
This isn't a perfect analogy, but it's kind of like saying a guy isn't a great runner because he tore his ACL and surgeons fixed it but it's still messed up, and saying he should've just never gotten the surgery.
You're blaming the medication when people with ADHD are already predisposed to not being able to complete things, have normal careers, and are at high risk for anxiety, depression and other things. You're just seeing what ADHD looks like.
Stimulant medications are not a cure, but they do improve quality of life in ADHD patients compared to baseline.