Has the Guardian gotten worse or were they never that good to start with?

Wildlife services is hardly a secret branch, they are also the folks who airdrop rabies vaccine in remote areas. Yes they do take game from helicopter as part of their population management. Hogs in particular are frequently managed by helicopter since they like to hang out on private property.

The M44 device does have it's issues but calling it a bomb is a gross misise of words - it's a spring loaded aerosol. It's typically used for pack management especially with hogs. Most of the concern with them is downstream of the food chain - a nontargeted animal eats a poisoned carcass, dies, and then something eats those remains.