Yeah. Something similar happened to my grandmother, though it wasn’t hospice. She was in a nursing home after a pretty much debilitating stroke in her 50’s. She was there for about 20 years, constantly mentally deteriorating.
Then a funny thing happened...
She went to a different nursing home and they took her off almost all of her meds and suddenly we had her back, at least mentally. The doctor who was in charge of her medication in the first home lost his license to prescribe drugs. Coincidentally, he was also the doctor that delivered me in 1954.
Wow.