W3C have zero power. Apple and Google have power. Also I don't think that DOM presents any problem to security. It makes no sense to cut DOM or JS engine from

W3C have zero power. Apple and Google have power. Also I don't think that DOM presents any problem to security. It makes no sense to cut DOM or JS engine from your sandbox. You can use Canvas/WebGL/WebGPU to access GPU and draw anything in browser window. You can use WASM to have good speed. Tech is already there, you don't need W3C for it and DOM or JS is not really in the way. Storage, Cameras, GPS, Mulththreading, Gyros are available for web apps. Everything is already there. Web apps miss notifications on Apple platform, home screen installation via API on Apple platform, better integration with OS on Apple platform (not sure about Android), but probably you want your password manager to be native app anyway.