Recency illusion
The recency illusion is believing that a word, habit or trend is new when it has been around a long time, simply because you only recently started noticing it. It is closely related to the frequency illusion, where something seems to show up everywhere once you notice it.
The term comes from linguistics, where it rests on many documented examples rather than on controlled experiments.
In everyday life
Someone complains that using 'literally' to mean 'very' is a modern sign of declining language, though well-known writers used it that way in the 1800s.
You notice lots of people wearing a certain style of sneaker and assume it is a brand-new fad, though it has been popular for over a decade and you only just started paying attention.
Why your mind does this
Our ancestors survived by spotting patterns fast: rustling grass might mean a predator, and dark clouds meant rain. Filling gaps with a plausible story lets us act on thin information instead of freezing. A brain that sometimes sees a pattern that isn't there loses less than one that misses a real threat.
Its family, in 30 seconds: Stories & patterns
How to spot it
Ask whether the thing is truly new or whether you have only just started to notice it.
How to counter it
Look up when the word or trend first appeared before claiming it is a recent development.
Same family: Stories & patterns
SourcesRickford et al. (2007)·Wikipedia