Then there is TFY,S! which is more about actual independent thought, questioning everything and expunging as much bias as possible. Conclusions may not be the goal... perhaps its more about thinking about, questioning and poking at all thought and all bias.
I might be coming at this from too utilitarian of an angle. I think of TFY as something that has both pragmatic benefits and as something that's fun to do in its own right, like higher math and strategy games. You certainly need some minimum level of math to function effectively, but it would be weird and selfish to convince people to learn higher math just because I personally enjoy it.
I see the value in practicing independent thought, but it doesn't follow from that that other forms of thought are valueless. I think it's an error to disregard the "social mode" of thinking - humans are social animals, and social signaling matters. People really do soak up thoughts and opinions just as they emit them, and that's okay. That's how people work.
As an individual, you can improve on this somewhat by being selective as to which ideas you internalize. As a member of society, you can improve on this somewhat by being selective as to which ideas you encourage or discourage in others. Everyone does both all the time; to a greater or lesser degree, we think for each other, in a very literal sense. It isn't something that can be avoided short of dropping out of society, and even that has the "silence indicates approval" thing going.
I wouldn't go so far as to say that it's a zero sum activity, but there is a tension between how much of an individual's thought is "independent" vs. how much is "recieved" - by socializing each other, we leave each other less room to think for ourselves. That's a conflict we should recognize and be mindful of, and not try to cheat with simple answers like "never tell someone else what to think." I don't think any quantitative solution ("think this much for yourself, accept this much opinion from other people, and do that much shaping of others' opinions") will work, actually.