You are aware that grannies get raped aren't you?
Just because they are old and crinkly doesn't mean they are safe from sexual abuse.
Unfortunately because they are vulnerable they are a target.
Don't forget some men actively placed 'fuck a pig' and have a mentality of 'any goal is a hole'.
Did you think this type of man suddenly developed morals, standards or respect for women after they reached a certain age?
This is the first result I got from Google on the subject. It says that sexual abuse of the elderly is more common than you think with one of the problems being that victims often can't report the abuse or are not believed. (You are aiding that culture here with your disbelief)
https://www.nursinghomeabusecenter.com/elder-abuse/types/sexual-abuse/
The common offender? A carer.
I could have picked many other articles on the subject. This is just the first I looked at. It's widespread and a known significant issue.
Given that patterns of offending do not change following males transitioning, we absolutely should be worried about ALL male carers of women regardless of the age, disability or mental capacity of that woman (or girl).
I'm sorry if this comes as a shock to you, but it's not MN providing this low. We are just aware of the problem, you don't want to acknowledge and you are actively shooting the messenger on this subject.
Go away and do some research.