FOMO potential?

For now the SPX is stuck in some sort of consolidation, down around 140 points from recent highs, and up around 180 points from recent lows close (excluding the huge intra day low print in mid Oct at 3502). SPX is unchanged since Sep 21 basically. Nobody is in control yet, but the crowd has "filled up" money market funds. What happens in case the Santa rally kicks in?