Yes, there are concerns about EVs towing stuff around. As highly efficient vehicles, electric automobiles may have more issues with that than combustion-engined pickup trucks, but they also have issues with that.
Our editor in chief Eric Loveday has a Ram 1500 eTorque and a camper that is “only 15 feet long, 1900 pounds and about 8.5 feet tall.” It normally goes 520 mi on a full tank. When it tows the camper and there are winds at highway speed, it will only get about 220 mi of range.
Tesla is probably considering all that, as well as how to allow supercharging with an attached trailer. What people cannot say without evidence is that it will not be a vehicle suited for towing. Not yet, at least.