Airplanes have stringers and supports to hold shape, not foam cores. They also have protective uv coatings and/or paint.
Car interiors get way hotter than any lake I know of.
What temp do they press the skis when manufacturing them? For how long? Can the rocker change if you heat it and press on it? Ive seen a guy change tail rocker that way.
The industry professionals that told me not to leave the ski in a hot car were pretty adamant about it.
I don’t know for sure, but I am not leaving my six season, one of a kind irreplaceable ski in a hot car.