This is only because you are shining a spotlight on what they perceive as something they are not doing and at a very real level it bothers them. Those that rise to great levels are always criticized yet behind the scenes the person criticizing is simply reflecting there lack of self esteem.
Truly confident people seek to build each other up. This is why the most successful in any arena choose to hang alone or with other successful people. Easier to stay motivated and happy with like minded folks . That old saying misery loves company always seems to have merit.