Yes, Jean dies at the end of Morrison's run but to imply that she ends it anything close to being a loser is quite literally a lie. That's literally inventing something to fit your narrative when the truth of the matter is that there was no single character that was actively elevated during that run like Jean Grey was. Even if you agree with the idea that she was almost treated as perfect, which I don't, saying that she was a loser goes against all of that. In Morrison's run Jean: stopped the U-Men almost single-handedly when tapping into the Phoenix power for the first time since the Dark Phoenix saga, survived against and helped stop Weapon XI while also being one of the only ones that survived that encounter, helped stop Cassandra Nova and saves Charles Xavier's life multiple times, including taking his entire mind into her own (at the expense of some of his memories, but still), held her own against Shi'Ar super soldiers, single-handedly pieced Emma Frost back together, revived herself and Logan with the Phoenix Force after Asteroid M flew into the sun, converted Asteroid M's remaining metals into a space ship which she then used to travel the immense space between the sun and Earth, saved the rest of the team, and is the entire reason that they were even able to get to Earth to stop Magneto... where she was the only one that could stand up to him, and only died because he got in a lucky hit. And then after she died, because everyone seems to forget that this was our Jean, she woke up in a dystopian reality that using the power of the Phoenix Force she destroyed and then prevented.
Morrison's run was Jean Grey's best consistent showing in a long time, and that's coming from someone that doesn't hate 90s Jean.