lol... before you waste your time looking at apple spin, might help you to actually understand what the signal protocol is and how almost all the E2EE systems already do everything tehy are talking about except without the "post quantum" hooey

because, actually, i personally doubt that quantum computing is gonna matter until at minimum modular nuclear reactors are the norm, that's how much power it requires

and i seriously doubt that even then it will work because all forms of nuclear fission reaction produce masses of heat and that's the enemy of quantum computers, which need very low temperatures

the only way that quantum computers can happen is if we figure out antimatter energy, and by that point, well, i would argue that we won't be trapped on this planet either