I say probes would give similar GI quality because i would be disappointed from Metro not looking better than previous GI approaches with lesser hardware requirements.
If i would consider to upgrade GPU, i would expect significantly better visuals than ever before, after seeing Star Wars.
It's very difficult. Current games can show very impressive trailers, so NV had to show something like Star Wars to beat this.
But the few games do not look thaaat good, so likely people decide to wait with the upgrade until more games show, or until HW becomes cheaper.
At the same time people may even decide not to buy the games, because they want to wait until they have the HW to enjoy all features.
Gamedevs so also have a difficult decision if RTX is worth it or not, even if UE4 and Unity make it easy.
It will take some time...
But the promise of dynamic lighting is not to save work on probe placement or baking time. That's really a bad argument gamers do not want to hear.
The proper argument is the opportunity for new level design, or even new options for gameplay.
And that's exactly what's not possible until everyone has the hardware.
It is also a bad argument for developers, because they save no work by adding RTX support - it's just more of it.
And they know complexity is not going to decrease while performance is finite.
NV might consider to buy a game studio... but secretly, to prevent another stupid shitstorm