So that could be a clear definition, but for it to be "table stakes" it needs to have some universal value and it doesn't (in fact, that very same definition could also classify even C as "memory safe"): https://news.ycombinator.com/item?id=49087458
I'm not exactly sure what you mean by "universal value", but I would say to be "table stakes" (i.e. not optional), it has to have overwhelming value. I think outside some fairly niche areas (e.g. programs that don't process untrusted data at all), it very very clearly has overwhelming value.
Now you might argue that the other features of Zig, like `defer`, are so good that they reduce the chance of memory errors and therefore memory safety has less value for Zig. But that seems highly dubious to me, especially for use-after-free. I guess we'll find out when Zig has more widespread use.
His point is literally that writing a JVM (or any other language runtime) in Rust is unpleasant.
He can't write a JVM without using unsafe. So his disagreement on the "table stakes" is that his "table stakes" require using unsafe Rust everywhere and from that perspective Rust is not that different from any other language.
Hence the complaint about the lack of universality, which I personally consider weird. His point is that you cannot write the most interesting low level programs using just the safe subset of Rust.
If you have to write unsafe Rust (emphasis on have, your mileage may wary lot on that), then you have to litter unsafe everywhere in your code base so how does Rust help him? That's his point, but he doesn't want to say it out loud.
What makes a JVM a good fit for a low-level language is the need/utility for precise control over the hardware, but that's always the reason to want a low-level language (why would you use a low-level language if you don't want precise control over the hardware?). When Rust gives you safety it takes away much of that control, and when it gives you control it takes away the safety. Now, there could well be cases where this mix is fine - I've never worked on a browser, and Rust may well be the best language for writing browsers.
