Since primers from different manufacturers have different material thicknesses and materials, the evaluation of the gas pressure on the condition of the fired primer is not very helpful!
In addition, the primer does not know in which caliber it was loaded.
This should be obvious with the example .38 Spl and 357 Mag. A .38 Spl has a much lower permissible gas pressure than the 357 Mag.
If the gas pressure is exceeded with a .38 Spl, then the primer should have overpressure signs, but a 357 Mag would not have overpressure signs at the same pressure.
A meaningful assessment of the gas pressure can only be made by measuring the gas pressure.