There are degrees of ‘We’ it’s not just ‘I’ v ‘We’ perhaps. It’s certainly true that a manger who just leads with I is unlikely to get the best results from those led. The people led too though have to break out of an ‘Us’ v ‘Them’ attitude to their leaders, or it can’t work fully. The initiative lies to a great extent with the leaders but not all of it.
There is also the scope of ‘We’. People are complex and diverse, even when selected by a particular set of attributes. There will be folks within the ‘We’ who have different perspectives and disagree with each other, or whose personalities conflict. It takes a lot of maturity for everyone to tolerate these differences. There is a tendency for any We to break up into Thems and Us’s and I’s. Most leaders are not gifted with the social or political skills required to bring the group together into harmony in the face of these personality and perspective conflicts. The best they can do is form an inner We of people who support them and just tell the others what is what, in order to get the job done. I guess that’s the best practical possibility in most real life situations.