I see results like the OP as speeding up progress. Tests like ptau make it faster and cheaper to screen for participants in clinical trials. This allows more resources to be spent on pre-screening, to identify candidates that might be healthy at time of trial start, but who are likely to develop cognitive impairment during the trial, which can be helpful for better measuring efficacy etc.

There was a good, accessible guidelines paper in the Lancet that described helpful interventions at all stages of life to decrease the odds of developing cognitive impairment later in life.[0]

In terms of late-stage treatments to halt or reverse progression, that still seems very far away. The causes are so diverse... My father died of vascular dementia not too long ago, so I'm familiar with the caregiver side in addition to the business.

[0] https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

While AlphaFold is great, to my knowledge, these proteins have several non-significant IDRs (intrinsically disordered regions), which have been and continue to be hard to model with AlphaFold. I work on computational modeling, so if I had to guess, I'm very unsure if people are using it for whole protein modeling, rather than looking at more specific domains where it probably does much better.