True. To be fair, CHERI guarantees only security, while borrow checking (when it works) guarantees both security and correctness. If you write to a freed pointer or out-of-bounds, CHERI guarantees that your write either crashes or lands somewhere harmless, rather than corrupting other data. But borrow checking guarantees you won't perform such writes in the first place.

Yet while correctness may excite programmers, it's security that gets the decision makers' attention. At the end of the day, security is just much more impactful.

We'll see if Morello ever makes its way to the types of CPUs used on phones and higher-performance devices.

ARMv9 is not Morello and MTE is not CHERI, but it is much better than nothing and already in a few phones. But it does require software adoption and I don't know how heavily they've adopted it.

Yes but CHERI is supposed to work for every application, not only Rust, but your favourite game from Windows 95 era as well.