The documentation already labels LPV as “not ready for production”. If it’s mentioned anywhere as supported, those sources almost certainly predate the closure of Lionhead Studios and the sentencing of LPV to limbo.
You mean when they remove all the previous lighting in the entire engine and replace it with something that uses a completely different standard that is incompatible with all previous art styles?
Raymarching did not need any enhancement or modification to the engine, but it is only possible with custom nodes in the material editor.
While any GI implementation may take time, that it is explicitly not being worked on is what makes that hypethetical time period even more foreboding.
While I’m sure some optimism (or at least less pessimism) is warranted, somewhere, your justifications for optimism are so thin that it only encourages more pessimism.