You now plan a new date in January, knowing Omicron is spreading and countries are starting to close their borders once again, and knowing Kourou had to be closed for like 6 months already once because of COVID, preventing any launch.

Do you want to take the risk of your 11B$ payload maybe getting stuck in a hangar for 6 months? Any issue with the ventilation, de-humidifiers or hundreds of other things could potentially damage it.

Then you bring everyone back on site, and now you have to reinspect everything, rocket and payload and restart the whole process, move JWST back again into the assembly tower, again a risky manoeuver, and as always, many things including weather can make the launch window slides for days. Being stuck in Kourou for weeks is not as fun as it may seems.

So no, it makes 0 sense to move the date around for something non-critical, and I'm pretty sure everyone already on site would rather just get it done now and celebrate christmas with their family a few days late, than add unnecessary stress on JWST and themselves for potentially months.

No better gift than a successful launch. The folks working on preparations overnight surely see themselves as Santa's Elves in some fashion.