"Secure Java" is something I recall hearing decades ago. No idea if it still exists. The more important thing to consider, however, is the fact that CLR, JVM,

"Secure Java" is something I recall hearing decades ago. No idea if it still exists. The more important thing to consider, however, is the fact that CLR, JVM, etc. provide internal memory safety whereas Wasm runtimes don't. e.g. a C program that goes sufficiently out of bounds on an array is guaranteed to segfault in the C runtime, but that runtime error does not necessarily occur on a wasm target. That is to say, the program in the sandbox can have totally strange runtime behavior -- still, defined behavior according to wasm -- although the program has undefined behavior in the source language. In the case of JVM languages, this can't really happen.