Against something whose dodging is stupidly good (Ships with 3+ agility and relevant die manipulation, like the meta-defining Phantoms), the 1 point spent on Munitions Failsafe becomes a hard counter.
Or just a wasted point. A player that brings a ship that needs to avoid stress is going to focus fire on your stress source and kill it ASAP, which means you'll be lucky to use both shots even without the failsafe.
The enemy MUST either Take the Damage, which they really don't want to do, or let me keep stressing them, which leaves them supremely vulnerable to the other 69 points of my fleet.
Or just kill your b-wing. Remember, you have 8 HP, one green die, and no defensive upgrades or meaningful arc dodging ability. It's incredibly optimistic to talk about "keep stressing them" when your stress ship is probably off the table in 1-2 turns. For example, a phantom list can send its support in first to damage Nera (and you don't really care if an academy pilot takes stress), then once she's damaged the phantom comes into range and kills her in one shot. That is, if the support doesn't finish off the b-wing itself before the phantom gets a chance.
It assumes that the enemy is consistently able to stay out of Range 3 during Nera's target-lock, and is then able to move in for the kill.
This is actually a pretty good assumption in the early turns (and Nera is unlikely to survive until the late turns). At PS 5/7 you move before most of the ships that really care about stress, so very often you'll be out of range when you end your move and then watch helplessly as they move into range with theirs.
For Deadeye to be better than Veteran's Instinct in this case, their key-ship must be at PS 7+ (in this meta, a viable concern). For it to be better than nothing, 5+.
But most key ships ARE at PS 7+. Phantoms are PS 8-9, most phantom counters (Wedge, Corran, etc) are PS 9-11, Jake/Tycho/Fel are PS 9-10, etc. This metagame has been absolutely brutal on mid-PS ships, most of the time you're either facing PS 8+ aces or PS 1-2 generics. And the few mid-range ships you might expect to see are "jousting efficiency" ships like x-wings that are happy to do green maneuvers to clear stress every turn. VI on a PS 5 ship is almost always a waste right now.