Do proton bombs Bypass shields and give crit-damage despite shields on a ship?

Yes.

To elaborate on that answer a little bit...

Proton bombs don't cause "damage", they deal the target a face up damage card, so things that interact with damage (such as shields) don't work on them.

Something that says it causes damage will hit shields, something that deals cards won't.

Thank you kindly for the elaboration and thorough explanation!

From page 4 of the most recent FAQ, top right-hand corner...

Suffer Damage vs Deal a Damage Card:

An ability or game effect that causes a ship to suffer damage is different from that ship being dealt a Damage card. Suffering damage occurs as described on pg 16 of the Core rulebook, and this damage is applied to shields first as normal. A ship that is dealt a damage card is simply assigned that damage card, regardless of how many shields it has remaining. For example, the effect of Proton Bombs deals one faceup Damage card. Damage cards dealt in this way cannot be canceled by evade tokens, redirected by Draw Their Fire, etc.

The proton bombs make me very happy to play against rebels, they just tear them to bits! :-)