It does. It will heat up. To quote a physics textbook: “Power transfer between a voltage source and an external load is at its most efficient when the resistance of the load matches the internal resistance of the voltage source.” IOW in the configuration where the power transfer is at its most efficient, battery has to dissipate as much thermal energy as motor(s) are consuming. Too much internal resistance and most of the thermal energy ends up in the battery. Too little, and your motors aren’t going to do their best. But in either case even with the load that’s not 100% matched, you do end up with a ton of heat dissipation in the battery when a heavy car like this is driven hard.
That sentence from the textbook is poorly worded, see https://en.wikipedia.org/wiki/Maximum_power_transfer_theorem...
Yes, power is lower when efficiency is greater all other things equal, but you work around that by not making all other things equal.
I'm not saying that Tesla has invented a sufficiently efficient battery, but to vaguely claim "physics" makes it impossible is wrong.