If you mean December 2021 and intend to do a
DVC reservation for that period, the first thing you need to do is check availability, because it is probable that both studios and 1BRs at every resort are already filled for at least some of the nights.
Other than that, it is difficult to say whether it is a crazy idea. My experience with NYE time at WDW has all been outside of covid periods and what might exist this December may be substantially different than pre-covid years due to covid created restrictions. I do not know what celebrations will actually take place and those may be substantially fewer than non-covid times. I also do not know the extent to which the covid crowd rules will limit the crowd sizes, which in non-covid times were extremely huge. In other words, I have no way to predict what might happen this year based on past experiences.
I have actually done NYE time a dozen times in the past and it is crazy if you go expecting to do a lot of rides and attractions and have problems with huge crowds. Think street crowds so thick that it can take 45 minutes to walk from Space Mountain to Splash Mountain at MK, and popular rides can get 3 hour stand-by lines, so you are essentially limited to fast pass rides and possibly finding something else if you go first thing in the morning when the park opens. (Note that the huge crowd times would last the first three days of your desired trip; thereafter it will drop off although still be rather large) However, the shows and parades are made for the holidays, the fireworks displays are extreme, some extra outside shows appear at parks, at least a number of the resorts have very good bands NYE (I have been to Jambo and Boardwalk events for NYE), and a number of EPCOT nations usually have much going on outside.
