He was 20-something when he lost his memory. So barely an adult.
And memory tests are not quite the same as dissecting his brain on television, then putting it on permanent display in grotesque life-sized cross-sections.
Further, he was institutionalized. So the guardians were - who? the doctors doing the dissecting?
You say "grotesque" in several of your comments, but this is a value judgment that is not shared by all. After death, what could be more poetic than using the instrument of one's intellect, the brain, to uplift the intellects of others?
And you, as an educated 21st-century world citizen can make judgements like that for yourself. This guy arguably can't. That's the whole issue, ignoring semantic arguments about word choice.
And memory tests are not quite the same as dissecting his brain on television, then putting it on permanent display in grotesque life-sized cross-sections.
Further, he was institutionalized. So the guardians were - who? the doctors doing the dissecting?