Paul is explaining the condition of ALL MEN after the fall and after the law came, in comparison to what came after. Sin is not just a verb, it's a noun also. It's a principality that cannot be overcome through the law alone, which is why the Spirit was poured out.
What he is saying is, that since he acquired the Spirit, he has become aware of this struggle within himself with this principality, and THAT IS the thorn in his flesh. He could not get it removed, because he was a man born out of season, privy to revelation * that was not to be fulfilled during his time in a physical body (*the redemption of the body Romans 8 speaks of).
Just as the blood only covered over sins until Yom Kippur came and removed them, so we in HaShem's timeline are waiting for the spiritual fulfillment of such. What you cannot perceive without His Spirit, is that everything that He gave our people is being spiritually fulfilled since then, according to His timeline. Peace
Not that I wholeheartedly agree with every aspect of your above understanding, but nevertheless, I often find myself learning something to reflect on from and about these things from the Messianic perspective you have just laid the above out from.
As a result of other passages in Acts through Philemon, I hold that the thorn in Paul's flesh was the many persecutions he'd had to suffer from his countrymen.
At the same time, how you described the abundance of revelations caused me to reflect a bit more on their place in what Paul is relating not only 2 Corinthians 12's account but also, other pieces of it all in other passages of Scripture.
As he relates elsewhere, said revelations had kept him focused on his sense of mission no matter what persecutions he'd end up having to endure.
Even where he was when those revelations took place ended up serving the purpose the Lord had related elsewhere they were to serve.
Add to that that it is indeed a powerful motive for continuing foward despite great obstacles when one has in their possession information they have committed not to speak come what may.
And those words of his at the end of it all - words those revelations had empowered him to be able to utter one day - "I have kept the faith."
How had he been able to? In the Lord's "My grace is sufficient for thee; for my strength is made perfect in weakness."
So, thank you for your post despite our obvious differences in understandings, it resulted in cause for further reflection on these things in ways I'd not pondered on til your post.