1 John 2:2 And he is the propitiation for our sins: and not for ours only, but also for the sins of the whole world.
I do not deny the truth of 1 John 2:2 ... I do not agree with your misconstruction of the verse.
The efficacy of the sacrifice of the Lord Jesus Christ is sufficient for the propitiation of our sins: and not for ours only, but also the sins of the whole world. The fact that some do not benefit from the sacrifice of the Lord Jesus Christ is the result of their suppressing/restraining the truth:
Romans 1:
18 For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold the truth in unrighteousness;
19 Because that which may be known of God is manifest in them; for God hath shewed it unto them.
20 For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, even his eternal power and Godhead; so that they are without excuse
In vs 18, the words "who hold" are translated from the Greek word katechō which means to hold back, to restrain.
In vs 19, we see what it is that men restrain ... that which may be known of God ... for God showed it to them. God reveals Himself, His truth, and that truth, that revelation is suppressed and restrained. So it is mankind who restrains. It is not God Who causes mankind to suppress/restrain.
In vs 20, God's eternal power and Godhead is suppressed, restrained, rejected and that is why they are without excuse.