Density said:
That seems to be more of an out-of-universe explanation.

Actually if you want an out of universe explanation you could just call it a big plot convenience. The thing I linked you two is a story (aka in universe) reason for why R2 suddenly wakes up when the plot requires him too.

I don’t see how it rules out that in-universe explanation. I still think Luke instructed R2 to only show the map when his daughter was there.

They could do both but the thing I posted is technically canon while R2 waking up just because of Rey’s presence is merely a theory. A plausible one…but still a theory.