Sorry but you just don't get it. Are you that unable to consider I might be right and the math "wrong" (regarding representing ultimate truth)?
WE KNOW THAT IN ETERNITY THEY WOULD NOT REACH IT. We know that they could do it for LITERAL INFINITY and not reach one. Because the fundamental function of the infinite series and which 0.999.. represents is, just as in each identical part, in the whole not designed to ever reach it. Since it just keeps on repeating a step where math itself says can't make it one no matter how many times.
All you have to say to that is "You don't understand infinity" I suppose I forgot that infinity is magic. So say the word. Or give another explanation.