There is a very big difference: ActiveX was native code that was literally running on your system with full access to system calls.
CheerpX is a Virtual Machine environment, it JIT compiles Wasm code from x86 binaries and it is fully sandboxed by the browser. It _cannot_ access your system even if it tried.
CheerpX is a Virtual Machine environment, it JIT compiles Wasm code from x86 binaries and it is fully sandboxed by the browser. It _cannot_ access your system even if it tried.