Frankly the question of the validity of so-called "Calvinistic-election" is made moot (as far as we are concerned) due to the fact that we are not equipped to recognize the "future elect" in our midst. Therefore the command is to preach to every living creature.
All that we see is what we may perceive as choice.
God's election is His business not ours.
This semmingly inscrutable paradox must not divide us.
Can we bury the hatchet and have an actual conversation? Logic for logic? Can we drop the ad hominem appeals to pathos and ethos? I think the content of your post here genuinely touches on a good point. Can we talk about this logically?
Your argument here is that because we cannot subjectively know who is elect or not means that the objective truth is irrelevant to our pursuits / not our business.
From an epistemological perspective, that can be a useful consideration for our interactions with the world. We really don't know who is elect and who is not, even if it were the case that there are objectively (metaphysically) those that are elect from the dawn of time and those that will never be elect (e.g. wheat and tares).
If you would now apply this same logic to Israel, you will see that we can't know who is actually Israel and who is not.
1) It is possible for someone not to know whether or not they are actually Israel
2) It is possible for someone to be a Saul to Paul Israel (currently antiChrist but set to become realized in Christ)
3) It is possible that someone appears to be Israel by claim but are not actually Israel (e.g. synagogue of Satan)
4) It is possible that someone is Israel and is Christian
But, out of these four possibilities, we do not have the capability to know the objective truth of the matter. We can't objectively know whether or not the current residents of middle eastern land are or are not Israel. We normally can't objectively know who can be saved, or who will be part of a spiritual people.
What does this lack of knowledge then leave us with? We should still abstain from the appearance of evil by not condoning antiChrists to continue being antiChrist. We should still be preaching to every creature including those that claim to be Israel. And we shouldn't anticipate that those making a man's claim to be Israel would actually be Israel objectively.
Do you disagree with the concept that your epistemological consideration for election would not also apply to spiritual identities such as Israel?