The market booms during the holiday season, and Christmas products like trees, light, and toys etc are the type of goods that sell a lot, but the only downside of begining a business at the verge of the year end is that customers tend to patronize businesses they've already known. Wouldn't the new establishment require some months of marketing before harnessing buyers?
That would be without a doubt a problem, since now that online commerce has taken off, it is more difficult to market your business as not only you are competing against the businesses around your locality, but you are competing against businesses around the world, so making your business known takes a lot longer than it used to, making me think you are correct in your assessment and this would mean that this is not really the best moment to start a business.