It was somehow IMO both predictable and implausible (having everyone on the same bus). It didn't ruin the film by any means but it definitely knocked it down a notch IMO.

Also, as you've said, Samir was completely opposed to the taking of innocent lives (he was against it in the initial bombing and argued against it when talking to Daniels) and there never was a point where you saw him understand that sometimes innocent lives were collateral damage. In fact, the last we saw him talking about it, he was kind of damning Daniels's character as being no better than the terrorists.

I think people can read into it and get something out of it but, for me, that moment of recognition/clarity for Samir wasn't there.