Strong maybe but rigid, no.
You'll notice that you only lift one corner of the car using these points i.e. the body is twisting.
In contrast, on my other car, either jacking point on each side lifts that entire half of the car so you could jack at the front to change a rear wheel if you wanted.
It’s about as rigid as it’s going to get considering the extra weight of the car and a big hole ( maybe ) cut in the roof for the sun roof ?.
The extra weight of the pack is a negative here alright.
In most FWD cars, when you lift the front corner, the same rear corner will likely rise with it.
The back end of a FWD car is extremely light.
This can be seen in tyre wear values.
Not with an EV !.
The pack is heavy and will therefore the rear end will be reluctant to rise like the front of the car.
These lifting points n the cill, are the same four lifting locations used by the dealer to pick up the car on a two poster lift.
When lifting up a convertible sport car on a two poster lift, if you need the doors open for any reason what so ever, you need to have them slightly BEFORE you lift up the car off the ground.
Otherwise you will never get them doors open once the car has left the ground !.
The car has a lost a lot of its structural strength because of the lack of the roof etc.
Same applies if you had the doors open, lift the car and they will NOT close now.
Ask me how I know ?.