Are you trying to say that code compiled with CFI is less vulnerable than code that wasn't? In which case sure, but that's entirely orthogonal to WASM. Code inside WASM isn't otherwise inherently protected. Code reuse attacks via indirect calls are still possible, as are of course side channel attacks and data leaks.

And since WASM uses linear memory and lacks things like ASLR, the code in the sandbox cannot achieve the same level of protection it could if it was in a hypervisor.