Thread safety, and memory model safety, and all this important stuff, is important! But ownership and lifetimes are models of reality that Rust asserts as part

Thread safety, and memory model safety, and all this important stuff, is important! But ownership and lifetimes are models of reality that Rust asserts as part of its domain language, which, like all models, are approximations of reality, not reality itself. They're useful to the extent that they help to solve a given problem. And not all problems fit into the assumptions that they assert.