"Tired of being compared to damn Britney Spears / She's so pretty, that just ain't me" ... that's the FULL lyric. I see no shade.
Pink supported Britney and mentioned many times in interviews that she likes her... she was one of the first to call her at that rehab place when Briney was going through all that sh*t a few years ago. Funny though you had to being up an article from 12 years ago.