On the one hand, "God's grace has been revealed, and has made salvation possible for the whole human race. (Titus 2)"
and on the other hand,
"But he that shall endure unto the end, the same shall be saved" (Matthew 24:13)
In other words, Christ truly is the Savior of Mankind, and died for the salvation of the World --- those are universally inclusive terms --- but we must enter and remain in a saving relationship with Him.
But I think no one can say ---as Patti Smith said 40 years ago, "Jesus died for someone's sins, but not mine." Perhaps she thinks she was predestined to be lost, which is (I think) a tenet of Calvinism, but in Catholicism would be called the sin of Despair.
But as I said before, I may be wrong about Calvinism. I refrain generally from commenting on Calvinst doctrine, since I don't know anything about it. really.
There certainly is tension between the two verses. But we do know that there are those who will not be saved, therefore He did not die for them. If he did die for them they would not be lost. Matters not if we are looking through a Calvinist/Augustinian lens or a more Arminian framework. (Saying the same thing as before, just rephrasing)
I’ll get back to you later when I get home and try to expand on that a bit.