Late onset Parkinson’s tends to present with dementia more than early onset.
If it was Lewy Body he wouldn’t be able to read the teleprompter at this point or know who anybody but Jill was. He’d be calling a dog a cat. The short term memory loss would be so bad he would be asking the same thing over and over every couple of minutes. My BIL has Lewy Body late stage and I’ve been observing it for about 9 years now on a regular basis.
Its likely Parkinson’s combined with some kind of dementia. In any case he has no business near the presidency.
I know what you mean about Lewy Body Dementia. My grandmother had it, and in the middle stages, she would have spells when she thought she was in Dublin as a girl watching the Easter Rebellion and the burning of the General Post Office.