Google is blocked in China, so I suspect that there are very few data points for Trends to draw on, as filtering the data to China, the graph seems raggedy, something like 4 searches/week. It also shows the spike in Haskell only occurred this week and says it is partial/incomplete data. So overall, probably just a data processing/extrapolation bug.
That's not to say that Haskell isn't used in China; there is a visualization group in Didi (Chinese Uber) that uses it, Haskell/FP user groups, university classes, etc. But there's no obvious reason that Haskell would have massively shot up in the past 3 days.
That's not to say that Haskell isn't used in China; there is a visualization group in Didi (Chinese Uber) that uses it, Haskell/FP user groups, university classes, etc. But there's no obvious reason that Haskell would have massively shot up in the past 3 days.