So the remote manager who won't reply to my emails or slacks, won't invite me to meetings with product / design, won't ask for my opinion on deadline dates and won't tell me whats being said in meetings (despite repeated effort on my part to change this);

Has decided to send an angry email, cc'ing a bunch of people, about "constant deadline slippage" and poor planning on our part focusing on features that should have been de-prioritised.

ahem
*clears throat for maximum yelling rant-ability*

<rant>
I HAVE BEEN EMAILING YOU FOR FUCKING WEEKS ASKING TO TALK ABOUT THE DEADLINES YOU FUCKING COLOSSAL ASS CLOWN.

I'VE BEEN REPEATEDLY TOLD THAT THESE FEATURES ARE A MUST HAVE AFTER ASKING TO DE-PRIORITISE THEM, AND HAVE TOLD YOU THE DATES ARE NOT FEASIBLE.

ONE MORE, ONE MORE EMAIL OR BAD COMMENT AND I'M EXPENSING A TRIP OVER THERE, TO KICK YOU SQUARE IN THE NUTS AS HARD AS HUMANLY POSSIBLE. I'LL HAPPILY BREAK MY FOOT OFF IF NECESSARY, YOU USELESS PIECE OF SHIT.
</rant>

... the above is work appropriate to email back to him and all the higher ups right?