I think Pokémon Go was a much more visible and impactful phenomenon (in certain places) than anything else on your list. This might be different to "cultural importance" depending on your definition.
I mean did random churches and libraries have "Playing Red Dead Redemption 2 is not allowed here" signs up?
Were there flash mobs in NYC playing Half Life Alyx?
I think Pokémon Go was a much more visible and impactful phenomenon (in certain places) than anything else on your list. This might be different to "cultural importance" depending on your definition.
I mean did random churches and libraries have "Playing Red Dead Redemption 2 is not allowed here" signs up?
Were there flash mobs in NYC playing Half Life Alyx?