Just people. CCC (constructive comments critique)

I think many of the comments to you pictures fit as answers to your question.

No it is not the equipment used. It is the fact, that you are not giving anything of yourself to the pictures; there is no explanation, no context, no way for the viewer to understand why you took this particular picture. We do not know why these people look so dissatisfied. It is just a bunch of pictures of people, taken without their knowledge or consent, not illustrating anything, not telling any story.

The long focal lengths are wonderful tools. They enable the photographer to isolate the subject by either blurring or leaving out of frame those distracting elements, that do not add to the picture. It is not the camera that takes the picture, it is you.

For a picture to arouse my interest, it must bear in it some kind of message, something I can relate to. It does not have to be "Don Quixote" boiled down to one picture, less will do, but there has to be something.

I don't know the legal circumstances in your country. I have just checked the rules here in Denmark, and although the rules leave room for interpretation, I doubt it would be legal to post them without the consent of the pictured persons. Personally I find it unethical, and I wonder how you would feel yourself, if you found your very unflattering picture on the Internet.

If you are shy and do not like to approach people to take their picture, maybe you should either find other, less complicated subjects, or practise your people skills on friends and relations who are willing to cooperate. What is your comfort zone might not be so comfortable to your subjects (or victims).