Hmmm. I would have to agree with many above. While TK FA's may often be forgetful, hard to find, linguistically challenged or whatever, rude is NOT something that they normally do/are.
Perhaps the OP is used to ultra fake Asian FA's who smile a lot, perform like robots, but in fact are not that great?
Regarding the lounge, yes it often is packed, although I must say that in my several hundred times in Tk lounges I have never seen them trash strewn or however he describes it. Perhaps the OP can post pictures? As for shower wait, etc. I see the same complaints all the time on most airlines forums if the poster is part of a big connection bank. That's life.
OTOH, the OP was flying PEK-MIA. A Biz fare with TK can often be had RT for this route of somewhere between $2500-4000. How much are the UA, AA, or DL options? Three times the price? Or if the OP went with Air China, Southern or Eastern, at least part of the way, I shiver to hear what the OP would have posted, I have been in all their lounges and they all pretty much are the most basic of basic.
We all know that the TK of 2017 is not the pre-June/July 2016 TK, and I am not normally a big TK cheerleader, but fairness, proportionality and reality have to be factored into this.