Omicron likely had a dampening effect on December activity in the US. There were also credible reports that Christmas shopping was pulled earlier so it's likely to be overestimating the contribution from the consumer.
We're just barely out of Q4 now but I'm comfortable saying that it doesn't matter. It's all about omicron, inflation, the Fed and China right now. The consumer is solid, there's plenty of pent-up demand and the saving rate is high.
The reason for the dip in the tracker, via the Atlanta Fed:
After the December 23 GDPNow update and releases from the US Census Bureau and the Institute for Supply Management, a decrease in the nowcast of fourth-quarter real government spending growth from 2.6 percent to 2.3 percent was slightly offset by an increase in the nowcast of fourth-quarter real gross private domestic investment growth from 16.9 percent to 18.0 percent, while the nowcast of the contribution of the change in real net exports to fourth-quarter real GDP growth decreased from 0.46 percentage points to 0.0 percentage points.