Why have we been going sideways for a month?

With just how volatile everything was just a couple of months ago before this sideways market, this seems hard to believe. It's been like this the whole December, happened right after that dip to 40k BTC.

Thinking about how BTC broke it's ATH not that long time ago, it's strange that there are more selling than buying, which must be the cause of this market but why exactly did people stop buying or the amount of people that sell are this much?

People do contribute it to a lot of factors though, like all the regulation news and as such but we've always had those, can't be that.