While I appreciate you saying that, I would like to say that I have likely been playing as her longer than anyone on this forum. Maggie used to be pretty much all I played. I know that particular character very well, so it would be pretty disappointing if I could not do well with her.
The problem I have with Maggie currently is the same problem I have had with Caira for a long time now: everyone does her job, but better. E-Griff locks down a monster about as hard as she does, does double her damage, and allows the team to chase. Crow and Abe both do like four times her damage while providing moderate cc constantly. Jack can utterly shit on a monster with his CC provided he has good timing, and still does more damage than Maggie.
Maggie used to be the absolute end-all of CC. No one else could compete with her ability to utterly shut the monster down with her harpoons. In Legacy, this was extremely good, because it meant mitigating was harder, and enabled bunker comps to be almost unstoppable. Because her CC was so good, she could afford to have low damage, as the comp could survive long enough to make up for it. That is no longer the case. Monsters do not mitigate anymore, pillars are almost non-existent, there is little cover for her harpoon traps due to maps being more open, and defensive comps can no longer sustain themselves against a competent monster consistently enough to justify giving up so much damage.
tl;dr Maggie’s current state would be fine in Legacy, but it does not cut it in the context of stage 2 and when compared with every other trapper. There is no reason to pick her right now.