My mother (85), a very intelligent woman though almost certainly with NPD, moved to AL near us three years ago and basically devolved responsibility for her life to my husband and me (without asking us!). Never sociable or outgoing, like many older people she has suffered mentally from the lockdown and is getting more and more confused and mentally lazy. She won't read a book, says she can't understand official letters any more and at times forgets who her great-granddaughters are.
There is vascular dementia in her family but we have no idea whether these symptoms amount to the onset of that or just the effects of lockdown on an already negative personality. It would be very hard to get a doctor to assess her and we don't have POA yet.