Also, regarding the tire....
An uninflated tire on a wheel with no vehicle weight on it looks almost the same as a tire inflated to 35psi, meaning it expands very little. Outside is still 15psi. There is only slightly more outside surface area exposed to 15psi vs the inside surface area exposed to 35psi.
How is that equalized?
A flat tyre on a rim has the strength of the tyre plus an equalisation of pressure. It's part of the environment it's in. Touch it and it will squash very easily because you are upsetting the balance.
A tire with the valve open is 14.7 inside and out, yep, got that.
My question though that you didn't answer- how do you consider the inside and outside 'equalized' when the inside is 35, the outside is 15, the difference in inside and outside surface area is minor, and there is very little actual expansion when inflated from 15 to 35?