He didnt die for all mankind, He died for all who He reconciled to God by His death and shall save by His Life.
1Jn 2:2 and He
Himself is the propitiation for our sins; and not for ours only,
but also for those of the whole world.
Who did Christ dies for BF
Joh_3:17 the world
Heb_2:9 every man
1Jn_2:2 the whole world
1Ti_2:5-6 for all
1Ti_4:10 all men
Rom_5:6 the ungodly
Rom_5:8 sinners
2Co_5:14-15 for all
Rom 3:23 for all have sinned and fall short of the glory of God,
Thats not what Rom 5:10 says, so you made a false statement not in the text
Rom 5:10 For if while we were enemies we were reconciled to God through the death of His Son, much more, having been reconciled,
we shall be saved by His life.
reconciled to God
"The verb means primarily to exchange; and hence to change the relation of hostile parties into a relation of peace; to reconcile."
VINCENT'S WORD STUDIES
"In the Christian sense, the change in the relation of God and man effected through Christ. This involves, 1. A movement of God toward man with a view to break down man's hostility, to commend God's love and holiness to him, and to convince him of the enormity and the consequence of sin. It is God who initiates this movement in the person and work of Jesus Christ. See Rom_5:6, Rom_5:8; 2Co_5:18, 2Co_5:19; Eph_1:6; 1Jo_4:19. Hence the passive form of the verb here: we were made subjects of God's reconciling act. 2. A corresponding movement on man's part toward God; yielding to the appeal of Christ's self-sacrificing love, laying aside his enmity, renouncing his sin, and turning to God in faith and obedience. 3. A consequent change of character in man; the covering, forgiving, cleansing of his sin; a thorough revolution in all his dispositions and principles. 4. A corresponding change of relation on God's part, that being removed which alone rendered Him hostile to man, so that God can now receive Him into fellowship and let loose upon him all His fatherly love and grace, 1Jo_1:3, 1Jo_1:7. Thus there is complete reconciliation. See, further, on Rom_3:25, Rom_3:26."
VINCENT'S WORD STUDIES