I didn't write
this, but I certainly sympathize with the author's feelings:
Dear Miss Manners:
Is there a polite way to tell my boss that "thx" instead of "thank you" or even "thanks" at the end of an e-mail kind of defeats the purpose? Thx.
Yr wlcm. And it is going to get worse as written English twitters away. Miss Manners is sorry to have to tell you that you are bound by the rule against criticizing others, and the likely consequences of criticizing your boss.