> WebAssembly doesn’t include a system interface, i.e., any way to interact with the outside world

I believe that's WASI, which builds on top of the base wasm spec: https://wasi.dev/interfaces#presentation

e.g. the WASI 0.2 spec here mentions clocks, filesystem access, creating sockets, etc.

Lua is architected the same way - As host, you create a Lua VM with no I/O, and then the host decides which I/O interfaces the VM can or cannot see.

JRE and .NET are probably built the same way internally. The reason wasm is hyped more than VMs with a decade of momentum behind them is that wasm is lower-level, it isn't tied to any particular GC model, and there's already backends for popular low-level languages like C, C++, Rust, and Go to compile into wasm modules.

Like this?

"More than 20 programming tools vendors offer some 26 programming languages — including C++, Perl, Python, Java, COBOL, RPG and Haskell — on .NET."

From https://news.microsoft.com/source/2001/10/22/massive-industr...

"The Amsterdam Compiler Kit (ACK) is a retargetable compiler suite and toolchain written by Andrew Tanenbaum and Ceriel Jacobs, since 2005 maintained by David Given.[1] It has frontends for the following programming languages: C, Pascal, Modula-2, Occam, and BASIC."

"Maximum portability is achieved by using an intermediate language using bytecode, called EM. Each language front-end produces EM object files, which are then processed through several generic optimisers before being translated by a back-end into native machine code. "

From https://en.wikipedia.org/wiki/Amsterdam_Compiler_Kit

"When IBM i was first released as OS/400, it was split into two layers, the hardware-dependent System Licensed Internal Code (SLIC)[15][1] and the hardware-independent Extended Control Program Facility (XPF).[16][8][33][34] These are divided by a hardware abstraction layer called the Technology Independent Machine Interface (TIMI). Later versions of the operating system gained additional layers, including an AIX compatibility layer named Portable Application Solutions Environment (originally known as the Private Address Space Environment),[5][35] and the Advanced 36 Machine environment which ran System/36 SSP applications in emulation.[1]"

From https://en.wikipedia.org/wiki/IBM_i#Technology_Independent_M...

Other examples can be retrieved from annals of history.

Yes, I discussed WASI in my comment. It has maybe 1% of the feature set of the JRE/.NET core libraries, and I think that’s a generous estimate.