That's nonsense. If Carrie Fisher "withdrawn consent" of her depiction in Star Wars, should we destroy the movies, all Princess Leia fan art, etc?

No, because the replacement value of those things to others is very high, and generally outweighs Carrie Fisher's objection. But we should take her objection into consideration going forwards. The Lena test image is very easy to replace, and it's not all that culturally significant: there's no reason to keep using it, unless we need to replicate historical benchmarks.