See, there is this word again in scripture 'called; that you don't like to talk about in your posts.
You're talking human wisdom and reasoning here, I will stick with scripture to understand the atonement, and you should also.
Hebrews 9, and notice verse 15 absolutely qualifies for whom the blood atonement is for this sprinkling of Christ's blood.
11 But Christ came as High Priest of the good things to come, with the greater and more perfect tabernacle not made with hands, that is, not of this creation.
12 Not with the blood of goats and calves, but with His own blood He entered the Most Holy Place once for all, having obtained eternal redemption.
13 For if the blood of bulls and goats and the ashes of a heifer, sprinkling the unclean, sanctifies for the purifying of the flesh,
14 how much more shall the blood of Christ, who through the eternal Spirit offered Himself without spot to God, cleanse your conscience from dead works to serve the living God?
15 And for this reason He is the Mediator of the new covenant, by means of death, for the redemption of the transgressions under the first covenant, that those who are called may receive the promise of the eternal inheritance.
Now for those NOT called, they will not be receiving this atonement, the atonement of sin is ONLY for those called to receive the promise of the eternal inheritance. Not all are called. For all those God foreknew, only they are called, and all of them are eventually glorified with salvation to be with Christ.
And also I like 1 Peter 1 so much better than your human reasoning which is contrary to what Peter taught about the blood sprinkling, whom it is for.
Lets see these words elect, chosen, foreknowledge, sanctifying, obedient, sprinkled, blood. in action
1 Peter 1 New International Version (NIV)
1 Peter, an apostle of Jesus Christ,
To God’s elect, exiles scattered throughout the provinces of Pontus, Galatia, Cappadocia, Asia and Bithynia,
2 who have been chosen
according to the foreknowledge of God the Father,
through the sanctifying work of the Spirit,
to be obedient to Jesus Christ and
sprinkled with his blood:
Grace and peace be yours in abundance.
If any read that, they will immediately see that those who are elect, have been chosen, according to God's foreknowing them in love, through the sanctifying work of the Spirit to be obedient to Christ and sprinkled with His blood.
So again the truth of election, is to be called, chosen, this resulting in faithful obedience to Christ by the sanctifying work of the Spirit and therefore an actually experiencing the atonement of His blood sprinkling they receive for their sins
I really don't expect to convince you, there are no winners in arguing over scripture, God's word simply is as He intends it and this is not a matter of a private interpretation.
These and so many other scriptures should be ample evidence that only the called of Christ receive the promise of the eternal inheritance.