Nothing makes sense with the Raptors and the trade deadline. I think that this is a huge failure that will impact the franchise for quite a few years going forward. I'm trying to look at this logically because as a fan I'm extremely unhappy with where this team is and appears to be going.
Most of the points have been covered already here. I want to focus on some things which may not have got as much attention. (I didn't read everything, sorry for any duplication).
"The guys will grow/improve ..." For some players perhaps, but not if they don't play! Mainly though, Scottie is the one we need to improve, especially with limited draft picks in our collection now. If we roll with this core, will he ever become more than a fourth option who defers to his veteran teammates? He needs the space to become "the guy". That can't happen if we keep the core together. When we landed Scottie and then saw his potential, so many people said everything the Raptors do going forward will be to maximize Scottie Barnes. This has not been the case at all.
Masai said something about "we know the draft" defending trading the pick for Poeltl. I don't know if this got much attention, but it's concerning to me. It hints that the Raptors think they are smarter than everyone else and can find talent with lower/fewer picks. The Thad/Koloko deal last year already hinted at this. It's true the Raptors have had luck grabbing talent later in the draft, but, they don't really believe they're going to grab a Siakam or OG with every late pick do they? They have also drafted Flynn, Bruno, David Johnson, etc, as would happen to any other team. The higher you draft, and the more often you draft, the better your chance at getting impact players.
Talking about how much they wanted Poeltl: There's nothing wrong with wanting him. But there should be a limit on the price you're willing to pay. So many other players moved today, most without a first-round pick involved. One of my biggest issues with Bryan Colangelo was that he seemed to toss away draft picks like they were nothing. I never thought I'd see Masai and Bobby doing this.
Masai was uncharacteristically anxious during today's press conference. His answers were not convincing to me - I didn't think that he believed everything he was saying. With absolutely nothing to back this up, I do wonder if the Raptors did have something big happening but if fell through very late. If that is the case, I think he should have just said so rather than falling back on everything else he said. If that is what happened. I'd like to believe my theory because the alternative is that he believes everything he said about the team, which to me is much more worrying.
At the end of the day, I feel like not only did they miss a huge opportunity to capitalize on selling some guys before they leave or get raises, they actively hurt the team through the Poeltl trade. The team is a little better today, but much worse off in the big picture. Masai has done great things for the Raptors but that does not and should not insulate him for criticism for actions that have the reverse effect. Hopefully he can salvage this in the summer as he says.
EDIT: One final thing - Masai had more than enough goodwill that I believe he could have pulled off a rebuild without too much anger from the fans and media. (Ownership ???) If the path he has now chosen does not work, I do not think that will be the case if they need to rebuild in a couple of years.