But 2 Thess says the Man of Sin "sitting" in the Temple must be "revealed" first.
Did you forget about that?
Well it is Satan so no more mystery. There is no temple, so until it gets built, no sitting.
The fact that the church has fallen away is proof the the Adversary won, and convinced the church to look for a ghost called the antichrist. 2 Thessalonians 2:3
"For the Day will not come until after the Apostasy has come and the man who separates himself from
Torah has been revealed, the one destined for doom."
This is Satan. Now 2 Thessalonians 2:8
"Then the one who embodies separation from
Torah will be revealed, the one whom the Lord Yeshua
will slay with the breath of his mouth and destroy by the glory of his coming."
This is the false prophet. The first being separated the world from the whole Torah, not just the Law. The false prophet embodies this separation. Now 2 Thessalonians 2:9-11
9 When this man who avoids
Torah comes, the Adversary will give him the power to work all kinds of false miracles, signs and wonders.
10 He will enable him to deceive, in all kinds of wicked ways, those who are headed for destruction because they would not receive the love of the truth that could have saved them.
11 This is why God is causing them to go astray, so that they will believe the Lie.
When the false prophet comes, Satan the first "man", the Adversary enables this false prophet, and with false miracles. The church will already be apostate, and believe all the lies these two beings tell.
That Day of the Lord is the last 1000 years, but amils reject that point. So yes, before the last millennium, all of 2 Thessalonians 2 about Satan and the false prophet will happen.