On my test drive this was something I was very worried about, as I've had ventilated seats for my past 3 cars ... maybe 4... I can't remember.
Anyway on my test drive day it was 28degs and very muggy. The AC was set to 21 deg inside the car.
Both in the front and back I didn't find the seat warm ... nor did I even feel that long term I would sweat ... not once.
Therefore I can only conclude it either depends on your body or maybe clothing at a push ... I don't know. But I do know I was wearing a cotton shirt and had zero concerns ... if I did I would have paid for leather and ventilated seats.
Get a test drive if you are worried. You could always put the AC up to 22-24deg inside to make you warm up fast!
The car was on a charger at 400v+ and 300a+ (can't remember the actual figures) and achieving 130+kw. For no apparent reason this suddenly plumetted down to 5kw! The car was only at about 30% charge at the time.
Ok later he figured this out ... and it happens on a lot of other EV's like the E-Tron.
When the cable drops down after the cars CCS port, the weight can pull the the top connectors (in the type 2 part) out a fraction. The type 2 connectors on a CCS are only for data and not power (those are the 2 large DC one's below the type 2). As there is now not a solid connection the car assumes maybe the connection is weaker. Therefore restricts the power more initially then expect the connection to heat up more so throttle's it more later.
Holding the CCS connector in the car while the handshaking is going on fixes this issue. Bjorn has done this on other cars too ... and tried it on the Polestar right at the end of the stream at another charger.