Jesus offered Himself as the propitiation for the sins of the whole world.
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.
By Jesus' death on the cross God reconciled the whole world unto Himself, but that does not mean He saved the whole world.
2 Corinthians 5:19
To wit, that God was in Christ,
reconciling the world unto himself, not imputing
their trespasses unto
them; and hath committed unto us
the word of reconciliation.
God did His part in reconciling the world unto Himself and now it is up to every sinner to do his part in seeking to be reconciled to God.
2 Corinthians 5:20
Now then we are ambassadors for Christ, as though God did
beseech you by us: we pray you in Christ's stead,
be ye reconciled to God.