What do you think of the lack of mourning and reaction to Stephanie's death that Tim had? Do you think it was out of character and part of the editorial hate train towards Stephanie?
In a word: Yes. Steph's death got mixed up in two that would have more resonance with Tim and his place in the wider DCU. Conner, which was tied into the Teen Titans storyline, and his dad, which was done to create the stronger connection to Bruce. Steph, for all intents and purposes, was a character for Tim and Cass. Cass got more leverage from her death because she was in general so isolated from other DCU books at the time, so the death of a supporting character was given space to breathe. For Tim however, his Teen Titans stuff obviously focused more on the loss of Conner (and Bart) whilst his Batman stuff focused more on his father, because then the writers could pull him tighter to Bruce. Steph was therefore redundant as a narrative tool for Tim's development in his two books. Her death was simply not as important as Jack or Conner's, and I think it's disingenuous to try and argue otherwise.
However, I think there is room to play in-universe with Tim's comparatively non-reaction to the point where I think you can argue that it was perfectly in character. I am crossing into headcanon here, but this is how I try to justify it to myself in-universe.
With Conner and Jack, Tim is loud, screaming, sobbing, clinging to the dead bodies. With Stephanie, he is quiet, withdrawn, and does not get to see her, instead is relayed the information secondhand by Bruce.
He doesn't think of her individually, because then it will hit home and he'll start to properly lose it. He never deals with her death. With Conner you have the proper loopy story of the cult and the cloning and that giant mess. With Jack there's the ongoing storyline of the fake Uncle, being adopted by Bruce and the ongoing grief there.
Tim does not talk about Stephanie. To anyone. He stands at the back of her funeral, not getting close, not speaking to her grave to say goodbye. He refuses to talk to Cass about her. He rarely, if ever, blames her for what went wrong, instead quietly and quite furiously blaming Bruce. He has very tense conversations with both Bruce and Cass about this fact. He thinks of her only when thinking of the people he lost as a group. He can't conceptualize her as an individual; she's just one of many that have died.
I get the feeling, if you wanted, you could argue that Tim completely disassociated himself from Stephanie's death. I say this, because in the TT issue where Tim has to be pried open about his father's death after attempting to shove it down, so it's a similar thing, though obviously not the exact same.
He cannot, will not, think or talk about her, because then it becomes too real, and he feels more emotions than he knows what to do with. He knows Bruce will never initiate that conversation, and fully resents him for it, and never fully trusts Bruce again (if he ever did to begin with). His Titans friends didn't know her, didn't want to know her in some instances, and the tentative conversations with Cass prove that they are not on the same page with the understanding of what happened either. Maybe Tim doesn't trust Cassandra with his grief.
You know what happens when he is forced to think of Stephanie alone and not as one of many, many, loved ones he's lost?
He potentially hallucinates her. So that's not concerning.
You can argue against this but Steph had not returned to civilian life at this point, so she wasn't enrolled in his school (yet). Also his internal monologue refers to the way she walks which is a much more intimate thing than "I saw a blonde girl and Steph was blonde too". Idk, YMMV on that.
Also, the fact that his first response when seeing someone wearing that costume is to get really violent, in a way that Tim just... isn't normally. Like yes it is a triggering scenario anyway but this feels a bit more pointed. Finally the kiss after he sees her for the first time... I don't know. It can read to me as someone who maybe rationally knows Steph is dead, but empirically never acknowledged it. Tim never saw her, and you know what they say about the dead and needing to see the body...
Tim perhaps, in his heart of hearts, never properly comprehended that she was dead. Any attempts to broach the subject were systematically but also unconsciously avoided. She is only mentioned as part of a group. When he is confronted with a reminder of her not being alive he gets very violent. When he sees her alive, he kisses her, as if they had never been apart to begin with for over a year.
Like I genuinely think there was like a mental block with the concept of Steph and Death for Tim that year she was gone. Like error error, cannot run script sort of schtick.
But that's just a headcanon. I don't think the writer's cared enough about her, not enough for any of this to be intentional certainly.
