See my response to your similar, later question https://www.researchgate.net/post/How_do_theoreticians_predict_that_the_life_time_of_a_Proton_exceeds_1034_years?isAnswerFieldFocused=true . A proton created right now through beta decay does not have to predate the universe. Couldn't all protons be like that? Stable but arising from other particles since a big bang?