I mean, dementia is your brain not being able to recall your life, or in some cases stuck in a certain time period in your mind despite it being decades later.

This is completely incorrect. Not only are there many types of dementia, with Alzheimer’s being the most common, but the memory problems common to dementia are not at all specific to recalling “your life”. Alzheimer’s symptoms:

difficulty in finding the right word, difficulties with visuospatial ability, and impaired reasoning and judgment. In later stages the symptoms become more severe, and include greater confusion, and changes in behavior.

https://web.archive.org/web/20260304025025/https://www.thedailybeast.com/confused-trump79-forgets-what-country-his-father-was-born-in/

https://abcnews.com/Politics/trump-claims-uncle-taught-unabomber-offers-evidence-support/story?id=123833782

https://archive.is/Hfl3J

Here are just a couple examples that I can remember off the top of my head and quickly find online of Trump exhibiting dementia symptoms. There are literally dozens of examples publicly documented, and likely countless that have occurred behind closed doors or been covered up.