Hello!
I've been following towing practices outside of the US, where, admittedly both the RV rigs and tow vehicles are smaller and lighter.
From my gleanings, tow "capacity" is a fairly bogus concept; much more relevant is the rear overhang of the tow vehicle (meaning: capacity to become a lever when trailer weight transfers to it), hitch type (passive as opposed to active, which balances weight between trailer and TV), and vehicle torque at specific RPM. On top of that, center of gravity is a key characteristic affecting emergency handling.
The Tesla 3 is an ideal TV for a variety of reasons: a) short overhang, b) strong strong from zero RPM, c) low center of gravity.
So called "tow rating" refers to the J2807 standard, which doesn't actually rule out the Tesla 3 as a "non-truck." It is also interesting to note that US "ratings" for cars differ radically from European ratings for the same model. But these ratings have some different assumptions about tongue weight, loaded (gross vehicle weight) and so on, but in the end don't equalize (IOW, sedans in the US receive a lower rating than the same sedans in Europe). It is fairly widely known that the US manufacturers profit exorbitantly from marketing trucks and SUVs, vehicles with widely varying design and capacity, and most with a relatively high center of gravity—not ideal for towing.
In my conversations with insurance companies about tow vehicles I learned that insurance coverage and tow capacity have no connection whatsoever. Yes: that is scary, but that is the reality. You can tow anything with anything in the US. There should be standards, I agree, but having a vehicle with a 10,000 lb rating doesn't buy you more "security" than pulling an Airstream with a VW Golf.
Apart from range, the Tesla 3 could be a wonderful TV, or any Tesla for that matter. The larger X with its "5000 lb" rating certainly pencils out better, and it has suspension that might allow for more weight in the TV, which is convenient.
End of the day, the "ensemble performance" of trailer and TV are what matter, including braking (and it's a misconception that the TV breaks for the trailer—unless you're talking about a small, utility trailer). Trailers such as Airstreams all have their own electric brakes that are capable of stopping at least the trailer, if not assist the TV. Remember that a large truck (F350) is massively heavy and has to have massively large brakes just to compensate for its own weight; it has no inherent advantage over any well designed vehicle with appropriately designed brakes, and neither can stop a trailer and itself.
