As others are pointing out here: the cross-platform value-add of browser based apps is the GUI layer, not the code runtime. We've had the JVM for decades, and it even has a GUI layer, it's just a much less powerful GUI layer than today's web.
People have been trying to create a simple, native, platform-agnostic GUI layer for as long as GUIs have existed. Nothing but the web has ever come close to succeeding. It may be a flawed solution, but it's what we have, and it works, and I wouldn't hold my breath for a greenfield alternative supplanting it any time soon.
People have been trying to create a simple, native, platform-agnostic GUI layer for as long as GUIs have existed. Nothing but the web has ever come close to succeeding. It may be a flawed solution, but it's what we have, and it works, and I wouldn't hold my breath for a greenfield alternative supplanting it any time soon.