How do you come to that conclusion?

Damage should be stronger and enough for a kill on any foolish enough to step past it as a trap is obviously it's intended purpose. However sticking to player is not what this type of grenade does. That is an action for things like fusion, flux, and magnetic grenade. The grenades that don't do well unless they attach to a player, can not attach to anything else, and have that look and icon. Trip mine are meant to be like spike and lightning grenades in their use. Stinking to walls as a high damage dealing trap and deterrent to enemy. They share a similar shape and icon on the perk tree. And like those other grenades it should have a higher potential to kill on its own of course with damage falloff.

then other classes do not deserve 1 hit grenades.

Every class has one hit grenades

1 hit kill*, and no... Hunters do not.

Flux grenades