From what I know, the official reason why Wally isn't as powerful as in other incarnations (mental block notwithstanding) is because the accident he went through was sort of a "cheap copy" of the one that gave Barry his powers.
I also believe, but this is just me talking mind you, that Wally's "lack of speed" is sort of an equivalent exchange situation. Really, this is just a theory I have that I use to cope; nothing's been confirmed at all, but allow me to elaborate, please:
By this I mean that in most works (if not all of them, sorry, my knowledge is limited) Wally's parents were abusive—in Young Justice they clearly aren't. So that's led me to think that happier home life = less power. As in, a "you can't have everything" kind of situation.
But I insist, that's just something I tell myself.
Then again, it does feel a bit cheap that, from what I've read over the years, one of the reasons Wally mastered the Speed Force was so he could go back to Linda but apparently he can't do the same for Artemis. Are you seriously telling me a 5-year-long happy, stable relationship ain't worth shit?
Then again, as much as I'd love to have Wally back, the development in the last two seasons makes me seriously wonder how'd they pull that off and have it be satisfactory.
After all, much of Artemis' arc last season was tied to her grieving Wally, with her current relationship with Jason as further proof that she's slowly but surely moving on. Even if the death of the most important person in your life is a wound that will never quite heal.
Even if there are many different ways a reunion between the two can play out, will they really risk undoing all that? And what if they don't plan on bringing Spitfire back from the dead and have a devastated but understanding Wally trying to move with his life as well?
That can make many fans feel uncomfortable pretty quick.
I mean, I'm not sure what the general consensus regarding Gardita is (or was), but it is undeniable that BBRAE is a fan favourite—I must admit I am too hoping Raven will eventually be introduced and maybe develop some sort of bond with Gar, but that's unimportant—, and at least back in season 3 fans were very disappointed, even irked, Bluepulse hadn't become canon and would likely never be.
I hardly doubt fans will like it if they officially sink Spitfire—you'd think it'd be impossible to sink it lower than literally killing it, but what do I know?
Anyway, the point of all this is to say that as wonderful as it'd be to have Wally back, I still wonder how they'd manage to fit that into the narrative in a way that feels natural after almost five years (in-universe) of mourning.
But yeah, if he does come back, Wally deserves the ultimate example of the Taken a Level in Badass trope.
