it's only application is being s-modded onto XIV variants for ridiculously high armour that can't be pierced by most weapons in the game. Though it still gets recked by end game enemies which are simply too fast to be effectively killed by Low Tech before they manage to kite out all your armour.
In my playthrough I kinda reversed Shield Shunt, in that it removes shields still, but instead it gives 50% fire rate at the cost of gaining 25% flux costs, cause otherwise it felt out of place with SO variants, the one which Eradicator has for example by default, and it... Well, it's a long story, who cares.
in vanilla imo, Shield Shunt is kinda like HSA. It sucks for 90% of the things, but then there is some broken end game combo that suddenly makes it good again that everyone is aware of, but then someone walks in and is confused as to why people think something is bad when there is 1 SPECIFIC, well in this case a few (cause Enforcer XIV, Dominator XIV, Legion XIV, Onslaught XIV, but meh, probably not all of them tbh) that makes them go "wtf, Shield Shunt is good, you guys". And the argument of "WELL, IT MAKES UR SHIPS MORE AGGRESSIVE, SO IT'S GOOD, CAUSE I WANT MY CREW TO DIE INSTANTLY". Okay, sure. You're absolutely correct about that, can't argue.