Many people seem to think virtually any kind of language trend is undesirable.
If true, this is sad. Personally I applaud language changes that increase complexity (e.g. neologisms) and disparage ones that reduce it (words or grammatical constructions falling out of use; two words that mean different things being used to mean the same thing).
Not all language changes that increase complexity are useful. In many cases, the use of particular words, or ways of speaking, can best be understood as wasteful signaling.
Linguist Arnold Zwicky has named three linguistic 'illusions' which seem relevant to cognitive bias. They are:
Zwicky talks about them here, and in not so many words links them to the standard bias of selective perception.
As an example, here is an exerpt via Jerz's Literacy Weblog (originally via David Crystal), regarding text messages:
It is my conjecture that these illusions are notable in areas other than linguistics. For example, history is rife with allusions that the younger generation is corrupt, and such speakers are not merely referring to their use of language. Could this be the adolescent illusion in action?
So, are these notable biases to watch out for, or are they merely obvious instances of standard biases?