'Disrespect' is the wrong word. Anyone who disrespects a team that has won 4 of the last 7 World Series' (and 1/3 of all WS since 1920) is ignorant, to be charitable about it.
You don't like the Yanks (for whatever reason)? Fine. You're bored with the Yanks' success? Very understandable. But disrespect? No. .....At least, not for anyone who knows about the game of baseball.