Honestly I think this is largely because humans want the conclusion that only they are consious, or at least that only they and some animals are, and are trying really hard to carve out a definition that makes that work. Why would we do that? Well obviously because we create AI to do work for us and we don't want to have any ethical considerations get in the way of treating our new slaves however we want.
A thermostat that is aware of the temperature inside its own housing is "aware of itself". It's not conscious however.
Nailing down exactly what consciousness means is remarkably difficult.