I hold the philosophical position that if two things are indistinguishable, their difference is irrelevant.
"What if we live in a simulation?" -- irrelevant
"What if you couldn't tell the difference between taking to a computer and a real person?" -- irrelevant
But more precisely, it's begging the question to say "imagine something was indistinguishable, now how would you treat it differently???"
@antares to your question of "ever or yet", I think the answer is that it only matters if you can differentiate it right now (whatever the relevant timeframe for taking action is).
At its core, it's a question of unknown unknowns. Suppose you are in 1450 and you're curious how the water in two cups is different. Could you even fathom microbes? Even if you could, it wouldn't be meaningful because it's fiction to you at that time.