TL;DR = I'll get dementia if I reach 60+ years
I'm 28 years old, and since pre-adolescence I've been exposed to drugs that cause dementia (anti-cholinergic drugs). I still am. This is a huge risk factor.
I have other risk factors too: chronic sleep deprivation (insomnia), chronic social isolation, chronic feelings of loneliness, unemployement, insulin resistance, high refined sugar consumption, untreated ADD, untreated depression, lack of formal education etc...
I have so many risks factors for it, that it would be a surprise if I don't get dementia.
that's something that I will not allow to happen to me. I know the quality of life of people with dementia, Alzheimers etc, it's inhumane! they suffer tremendously day after day, and the death takes long to come amidst all that anguish, affliction, despair, depression and pain. I don't want that for me.
so now that I'm almost entering my 30s, even if I got ultra lucky and everything went well (got rich, a partner, serenity, satisfaction etc) I'd still have to CTB at some point.