[AlexanderHowl]

The problem with an civilization that spends 90% on its time on VR is that there is no particular reason to interact with the real world. Their computing is advanced enough to allow robots to do everything, their society is egalitarian and wealthy enough that everyone can endulge in VR, and their VR is probably good enough that sex in VR is anew adequate substitute for sex in real life. At that point, the only thing that prevents extinction would be subsidies given to couples who willingly detach from VR long enough to have real sex until the woman gets pregnant (assuming they do not just let women opt for artificial insemination while they are in VR).

In such a scenario, there is no particular reason for farms, as vatgrown nutrition is probably good enough. With subterranean settlements and buried communication and power lines, the planet might appear completely uninhabited (power plants and settlements can be located beneath the ocean floor to allow for cooling efficiencies and protection from surface threats). You could possible have the world being colonized for a few decades before the original inhabitants realize that they have been invaded.