It's either exactly the same, or it's gracefully degraded. You're asking for two opposite things at once.
For what it's worth I support the notion that fundamental functionality should be supported without Javascript, with good old form submissions.
But I also recognise that you can't get the exact same behaviour without javascript initiated background GETs and POSTs. Easy example: A scrollable map that streams in chunks as you move it.
Fair enough. The proposed VÜPF changes suck balls.