Hulk is made of flesh. Doesn't mean weapons that can blast through metal can hurt him. Same deal with Groot, "made of wood" is irrelevant compared to his actual showings of durability.
Also, Team Rocket hardly needs to take special measures against Deadpool. He doesn't heal *that* quickly. Blow him to pieces, and he's out of the fight.
So you are suggesting that Groot's wood body is stronger than steel. Interesting- under some circumstances plant material can be stronger than steel ( such as stretching).
But what are Groot's durability feats like ? How often do we see him get hit ?
We know he is highly resistant to projectile weapons because we see him getting shot by multiple bursts from the Kyln drones and that not having too much effect.
We see Gamora hack off both his arms - how special is her sword ? Well, since it came from Thanos it's probably quite advanced tech ( the only time she uses it against Thanos is an illusion, so it's hard to tell) although it does kill the pink monster at the start of GOTG vol 2.
We see both Gamora and Drax being capable of breaking his vines/tendrils, and Drax pinning him down and battering him.
But other than that how often do we see Groot tank physical impacts ( other than crashing spaceships) or energy blasts ? I've seen GOTG more than a few times and in my recollection....we don't.
As such, I don't think it's possible to completely discount Deadpool and Cable's weapons - maybe Deadpool's guns ( and probably his swords), but not Cable who has high explosives, powerful projectiles and energy blasts.
When have we seen Rocket blow an enemy to pieces ? We've seen him use a bunch of nonlethal booby traps that slowed down the ravages, ravager pistols, two collapsible rifles - one which tasered Quill and one which blasted Ego's tendrils - although not that effectively, and a rifle against the big pink monster which didn't do a lot. I'm not convinced that he can simply blast Deadpool into bits , because we haven't seen him do that to any other humanoids. He does gun down a bunch of Thanos' monsters during the Infinity War and Endgame battles, but they're disposable goons and even Hawkeye can slice them to bits with his sword.
The most significant advantage Rocket does have is flight - if he can stay at a distance and blast away, maybe pick off Cable from behind ( force field) before he blasts Groot into splinters.
I summary, I think people are vastly underrating Cable and Deadpool and overrating Rocket and Groot. However, I suspect I will be on the wrong side of the votes again.