Despite the interesting discussion, I think people are losing sight that it's not all about the tech, it's about the fact that pop, which is usually the basis of what even makes a nation, seems to be not really useful in Stellaris and even often just counter-productive.
Population brings basically all the problem you can get in your empire (happiness, revolts, ethic drift, starvation/food, etc.), but it's use is reduced to working tiles which bring the same resources than what you can get for much less hassle in space.
The very fact that people think of abuse like putting a single robot on a planet, tends to prove that yes population as a whole is annoying and best being limited - when you'd think that it's the source of an empire power.
So again, I'd say it should be used in much more situations and for many more things, so a player can feel he's actually expanding his power by growing his pop, instead of only preparing the headaches to come.