Of course it is geographically biased. Even here in ‘First World’ Canada my home province is a million square kilometers with large sections a blank canvas on iNat, due to them being unreachable without a float plane, helicopter or weeks long canoe expedition.
Even here it only takes a 30 minute drive to reach relatively undisturbed habitat (Not going into the whole discussion about what the habitat was like before European settlement).
Even within the trail systems etc, there is also the whole ethical question of observing what is on the trail versus even a 100 meters off-trail.