I believe your doctor is mistaken, you are the one with dementia. I'd get that checked out.
Moving your money to something else of value (bitcoin) purely for the reason of dropping under a "must not have $XXX in savings" is welfare fraud.
Technically yes but I don't give a shit.
I think it is good for someone to save a little for future hardships and I think it is a crime of our society that people who are dependent upon the system are not allowed to implement the most basic steps needed to bootstrap themselves, but must keep themselves in a position where they are dependent upon others.
Now clearly if you are investing half of your disability check each month there needs to be an adjustment, but I see nothing wrong with saving even 10% of it.