I’m old enough to remember a time when nobody said,
“a bit,” but just “a little,” for instance. So the question is at what date did everybody start with, “a bit”? And question #2, why don’t people look or feel embarrassed when they utter trendy phrases? I heard that there was an essay by a postmodernist philosopher who said that people are talking more and more like soap opera characters but they don’t realize it. I have noticed this too, that people seldom say anything that hasn’t been said before (Chomsky used to say every utterance was new and had never been said before, other than of course fixed expressions like cliches and trendy expressions; however, doesn’t it seem that there are more and more of these and less and less originality?)
Gertrude Stein said, “Repeating then is in everyone. Everyone is continually repeating…” and so forth, and
“some day there will be a history of everyone who ever was, is, or will be living; some day there will be an orderly history of everyone who ever was, is,or will be living…”
MAKING OF AMERICANS
3)Thus is it true that history has come to a halt, as is also said in postmodernist philosophy? Soon we will not need to make robots because we will just turn into them, saying and doing the expected things at the expected times?
I can’t remember a time when “a bit” wasn’t used. Of course, I’m only 18. But really, I don’t think “a bit” is a trendy phrase.
And you’re extrapolating the end of history from the usage of the phrase “a bit?”
The term “a bit” has been in English for at least three centuries according to the OED, so you must be really old. Could you give us an example of the sense of “a bit” and “a little” that you’re talking about? Your question is very vague and really more of an attempt to start a Great Debate than a General Question.
—Genesis, “Get 'Em Out By Friday” 1972
Genesis? Can’t get much earlier than that.
IANALinguist, but IMO the use of “trendy” phrases is based on the same thing that led to the use of language to begin with. I use standard words instead of making up my own because I want to be understood. This extends naturally to collections of words, both in the sense of grammar and phrases. I may use certain phrases, trendy or not, rather than construct original but synonymous phrases simply because it’s efficient and facilitates understanding.
For example, I may say “don’t go there” instead of “I prefer not to discuss that topic at this time”. I don’t do it to be trendy; I do it because I know it will be immediately and correctly parsed by the listener. With some listeners, I’d make another choice, choosing a phrase they would parse more easily.
And I don’t see how your conclusion that history has halted follows from your premise that everyone uses trendy phrases. The use of common phrasing doesn’t hamper originality any more than language itself does. Do you think we’d be more creative, spontaneous, and worthy of making history if we had a “Tower of Babel” situation where everyone spoke a unique language, unable to communicate with each other?
I am SO not interested in the topic of trendy speech. In fact, I haven’t been this disinterested since forever ago. 
It might not be the best strategy to complain that “People seldom say anything that hasn’t been said before” just before quoting or paraphrasing Chomsky and Stein.