I have been preaching for over 35 years and specifically called unto End Time Prophecy. I will never call anyone a false teacher unless I think they are really doing it with foreknowledge. We see darkly now. But we also have the holy spirit, when we are given something, we are supposed to KNOW, that we KNOW, that we KNOW, and I know on this brother. I am not just guessing.
The REASON (I am giving you the answer here) is because the MISSION of the Church is finished. Read Matt.24:14, when the Gospel has been taken unto the ends of the world, THEN the End (70th week) will come. We have no mission left. Why was Noah not TAKEN? Because Jesus was yet to be born. Why was Lot not TAKEN? Because Jesus was yet to be born. Why will the Church be TAKEN? Our mission on earth is complete, its judgment time. Read Rev. 14, the Angel PREACHERS THE GOSPEL to the world, and the Two-witnesses are testifying about God and about both his mercies and judgments. We are not needed per se. Now as to WHY there are Christians during the 70th week. Because God is merciful, QUESTION if you miss the Rapture, will you not give your heart to Jesus? Do you think that should still be an option? Because I do, and God is merciful, so that is why we have Christians during the 70th week. But they are not preaching the gospel, they will be running for their lives brother, most will be killed for not taking the Mark of the Beast, read Revelation 20:4.
I don't usually read Mark, I read Matthew, but that Mark 13:9-10 verse looks like it parallels with the Matt. 24:9:10 verses where Jesus told the Disciples that they would all be killed. You do understand Jesus was telling the Disciples (save John) that they would all be killed right? Matt. 24:4-6 is about 70 AD. Matt. 24:7-14 is about the Church Age, not the 70th week, end times verses 14 sats THEN the end will come. Verses 15-31 are all about the 70th week. Thus we get THREE MENTIONS of False Prophets for a reason. In verse 5 it's about the false messiahs the Pharisees/Jewish leaders would put forth as Political Leaders (they thought the Messiah would be a political leader, not the Sin of God) to try and defeat the Fourth Beast (Rome) fulfilling John 5:43. Verse 11 is about the Church Age false teachers, preachers etc. especially those who would kill the Disciples for blasphemy against their false gods. And Matt. 24:24 is specifically about THE False Prophet and THE Anti-Christ.
God TAKES the Christian Bride to Heaven to marry the Lamb, we are his bride, we completed our mission on this earth. The NEW Christians know they left it too late, now they will have to pay with their lives because they tarried. They will be doing two things, DYING or HIDING, they will not be preaching. Our MISSION is complete brother.
I think the whole "falling away" misses what is going to happen, I think it's already happening and people do not understand what it is, Europe FELL AWAY a long time ago, now we are doing it in the USA. It's about the culture when it gets to the point that good is called evil, and evil is called good like is happening now in the USA, the Church has failed, we have given over too much ground unto the enemy without a fight. This means the Church is accepting in many cases the evils of the world, going along to get along, some even participating, marrying homosexuals, advocating for abortion, etc. etc. It is like the Jewish High Priests who accepted Antiochus into the temple of God, where he profaned it by sacrificing a pig to Zeus, and his very name claimed he was god manifest.
So, I see the culture and the Church as getting away from the mission of Jesus and thus the Anti-Christ spirit starts taking over, readying the culture for the rise of the Anti-Christ, who is alive now, this is known by me, I saw that vision in 1986. As per 2:Thess. 2, that is about the Church DEPARTING before the DOTL comes and the AC also arises before the DOTL, thus there was no need for the Thessalonians to fear that they were in the DOTL God's Wrath. The same words used in different places don't have to mean the same thing, you have to look at the CONTEXT. In 2 Thes. 2 we see in the 1st verse it's speaking about the GATHERING TOGETHER UNTO Jesus. In Tim. 4:1 it's speaking about the Church and culture giving in to WORLDLY WAYS.
God Bless