It will be busy. You will still have the Christmas crowds, plus there will be the Disney marathon crowds coming in as well (and sometime there are dance/cheer contests around this time). I believe the 2023 marathon is the 5th-8th. People will come early for that and overlap the holiday crowds, and then stay after hoping some of the holiday crowds will head home. There should be a short window in which crowds lessen before MLK, and then that weekend will pick up again before the (traditionally) lower crowds begin, but who knows if those crowd calendars will reset next year or not. Weather should be nice, cooler (or downright cold) mornings and evenings with pleasant days and very low rain chances. Shorter park hours, and things closed for your future enjoyment.