well armory isnt working atm (what a surprise) but basically those ppl are complete idiots. u said u 'need' another 5k hp, so ill assume ur at ~28K which is MORE than enough to naxx. hell i did naxx with like 25k buffed when it first came out. im pretty sure u couldnt even hit a bit over 30k hp in naxx gear alone.
these ppl are pretty much insecure about themselves being fail and expect a group of ppl to carry their sorry asses thru naxx. its tru that pugs expect a 'higher' gear lvl for content, but to say ur not ready is a complete joke. u are well enough ready to do naxx with 540def and ~28k hp.
imo, these arent the ppl u want to be running with anyway tbh.
also, who is telling u that u arent ready for naxx? randoms or guildies? either way the need to L2play and step up THEIR game a bit