[imaginenore]

1) Because the pods are not designed to go that fast through the air.

2) Because in the case of an explosive recompression there might not be a tube anymore.

[dpark]

This is a hollow answer. "Not designed for" is an absurd claim for a thing still in prototyping. Same for the "explosive recompression" claim. You're making this claim about a system that doesn't exist.

I'm not bullish on hyperloop but I see no reason to believe that the engineers can't design a pod capable of not disintegrating in air, or capable of designing a track with a failure mode better than completely falling apart.