Suppose I have 3x of the 5V-30V DC-DC 4A buck converters wired up in parallel.

Say first buck the load is drawing like 3.9A (near max) and 5V, other two are drawing say ~2.4A (at 8.5V and 12V respectively).

What happens if one of the bucks fails?  Is there a “cascading current” problem?

Not just at runtime – but say even on startup/powerup and natural variations, suppose one ends up with too much current and turns itself offline.

I can’t really imagine it being a problem (to the loads), but was just curious on thoughts about it.