There are actually some medications that can slow down the progress/help maintain a certain level of cognitive functioning for longer. So early diagnosis is actually really important. If you have early onset Alzheimer's, it may not make that much of a difference, but, let's say you're 80 when you start to show symptoms, depending on how physically healthy you are there's a chance that starting meds right away could delay the worst effects until after you die a natural death.

That actually isn't true in many cases. They usually have a waiting period (like you have to have had it for a year or two), but they will pay out for suicide. You just can't go by life insurance and then commit suicide the next day.

https://www.annuityexpertadvice.com/life-insurance-pay-suicidal-death/