2020's consoles have been linked to chronically low stock since their launch. This might cause some concern among buyers wishing to have one ordered prior to the winter holidays. However, Best Buy has announced that it should have stock of the PlayStation 5 and new Xboxes available to buy online from December 15.
https://www.notebookcheck.net/Best-Buy-claims-it-will-re-stock-on-PS5s-and-Xbox-Series-X-S-consoles-on-December-15-2020.509393.0.html