It seems like it for me, for the two phrases are in parallel, and it would mean that the first all truly means "all people" but the second one would have a limited meaning. It doesn't work that way when phrases are parallel. Words contained in both phrases of a parallel structure must have the same meaning. Another example would be the use of "aionios" in Matthew 25:46 And these (who did not assist the needy) will go away into aionios punishment, but the righteous into aionios life.” If "aionios" means "everlasting" in one of the phrases, it also means "everlasting" in the other. On the other hand, if "aionios" merely means "lasting" in one of the phrases, it must mean "lasting" in the other.L2J you wrote:It seems to me that the crucial statement that might be interpreted different ways is "in Christ". In Adam all die. It seems natural, to me, to take this as meaning that all who are in Adam will die. It seems just as natural to understand the phrase "in Christ, all shall be made alive" to mean that, just as all who are in Adam will die, so all who are in Christ will be made alive. That doesn't seem like a huge stretch to me.
I think you quoted that in support of your thought that only those who are in Christ will be made alive. It might also be helpful to examine the verses which follow.L2J you wrote:And then in verse 23 Paul says,
"But each one in his own order: Christ the firstfruits, afterward those who are Christ's at His coming."
I have deliberately interchanged 24 and 25, for I thought perhaps Paul's thoughts came quickly as he became excited about future things, and that perhaps he was thinking ahead too fast. See if the following order makes more sense:
23 But each in his own order: Christ the firstfruits, then at his coming those who belong to Christ.
25 For he must reign until he has put all his enemies under his feet.
24 Then comes the end, when he delivers the kingdom to God the Father after destroying every rule and every authority and power.
26 The last enemy to be destroyed is death.
It seems that this passage declares that this "being made alive" begins with the firstfruits (Christ, and perhaps those others who were raised to life at that time), secondly, those who belong to Christ at His coming, and thirdly those who come under His feet during the reign of Christ, after which He will deliver the Kingdom over to the Father.
So perhaps you are right. Perhaps there is nothing in this passage which declares that those outside of Christ will be raised. If so, then the problem remains.
Related perhaps to the problem is the statement made by John (Revelation) in which he saw that "the rest of the dead did not live until the thousand years were ended."