That question is actually two questions. The first one, do you really need all wheel drive, is more about the benefits of AWD in general. AWD provides more performance and better handling, with slightly less range. Whether or not you “need” it becomes personal preference. If the concern is over winter driving, unless you get a whole lot of snow in, say, western Maryland, then you probably do not “need” AWD. But you do need winter tires.
Winter tires in rear wheel drive cars give you much more control in wintry driving conditions than AWD without winter tires. Teslas by their basic design handle very well already, but bad tires won’t help whether two or four provide power.