Can't say for sure, but it could be because speculation has historically been a major driver of volume and low volatility is bad for speculators. So while there

Can't say for sure, but it could be because speculation has historically been a major driver of volume and low volatility is bad for speculators. So while there's certainly been a good deal of ups and downs recently, overall the market has been, for Bitcoin, relatively boring. Also, a lot of the hyperbullish types might be wary of going all in again, having been burned before.