There are never enough donations because to donate often there are many requirements for a specific study, or many limitations like no unsolved diseases. There’s a sort of stigma attached to body donation, truthfully most death is ostracized in some form. There is no recent or official study on body donations, but it’s thought that less than 18,000 bodies are donated every year in the United States.
Something that is fairly uncommon in body donation is the ability to be both an organ donor and a body donor. If you’re signed up for both, the organs are harvested, it’s prioritized, which almost always renders the body useless for donation. This is probably the biggest struggle for me, because sometimes bodies are used in experiments like being dumped out of airplanes or other frozen then slowly sliced to have an extremely detailed image of the human body, and organ donation is more calm, more assured. The only thing that can be harvested before body donation on a regular basis is the cornea.
If body donation were more talked about more casually, then more people would feel comfortable doing it. Donating is cheaper, and more helpful to society than any other kind of burial