As an adult child of someone with Alzheimer’s and former caregiver of older cousin, who died from Vascular Dementia, I understand your position and agree. It's a personal decision, so I have told my siblings my wishes and put it in my Advance Medical Directive.

I arranged to have a growth surgically removed frim my cousin’s head once, even though she had severe dementia, because she kept picking at it and it would bleed. There was no way to make her stop, so removing it was comfort care.