FFXIV ARR Know your SHIT

I have been told that I am a bit.... Vulgar when it comes to noobs.
"Let us know when you feel like tanking, f*cktard!" WHM
"Do your F*CKING job!" LNC
"Vote him out--- NOW!" WHM
"Feel free to use Flash.  We won't mind." BRD
"No, let me tank. I'm better at it." THM
"Shittiest Tank ever.  Stick to dps." BRD
"I'm done. Vote this asshole out!" WHM
and so on....

 I feel that this scenario is legit.  This is a Level 50 Rogadyn (cough-cough tail-less Galka) in full Relic gear and weaponry. My experience as a 48WAR is simple: keep shit off of everyone else.  I'm not perfect, but CHRIST! Things were everywhere! It got to the point to where the other two party members were just ducking behind me.

I need to understand how in the holy *** you get to this point and not tank worth a ****? He can't speak English---- only Japanese-- which he states in English.... along with his insults towards me. He theorizes that I suck D.  The real questions is: "Who's the REAL D-sucker?  The guy calling you out on being a sh****tank.... or the sh**** tank who magically made it to level 50?  He must've been  really good at it, because his past parties kept his worthless ass.... and mouth.