The following contains spoilers for She-Hulk: Attorney at Law Season 1, Episode 1 "A Normal Amount of Rage," now streaming on Disney+.
Whenever there are two types of the same kind of hero in any comic book universe, comparisons of which one is "better" are inevitable. Comparisons of Hulk versus She-Hulk are to be expected with the arrival of She-Hulk: Attorney at Law. However, the Disney+ series clearly states that Jennifer Walters is a superior, better Hulk compared to Bruce Banner's.
Like Obi-Wan Kenobi when Alderaan was destroyed, readers may have just heard a million fanboy YouTubers cry out in terror and suddenly silenced. However, if the fact that She-Hulk is superior to Bruce Banner's Professor Hulk bothers anyone, don't blame Jessica Gao or even Kevin Feige; blame Marvel Comics circa 1981. In The Savage She-Hulk #11-#12 (written by David Anthony Kraft with pencils by Mike Vosburg), Jennifer Walters defended a pre-terrible movie Dr. Michael Morbius in court. During this two-issue story, Morbius was able to help "cure" Jennifer of the savage nature of her transformations. Thus before Banner and Hulk joined their personas in the books, Jennifer was already a "better" version of the Hulk. She-Hulk: Attorney at Law takes this concept and builds on it.
Rather than some contrived storyline in the series (that would require Sony loaning Jared Leto to Marvel Studios), the series just jumps right to Jennifer Walters keeping her own personality while she is She-Hulk. Not only that, but some quality in the way Jennifer's blood reacted to the gamma radiation she took on from Bruce allowed him to fully heal his Avengers: Endgame arm injury. Thankfully the show doesn't go too deep into sci-fi technobabble to justify this. However, one theory offered by Tatiana Maslany's Jennifer herself explains why She-Hulk is so much better than Hulk: she's a woman.
Bruce Hulksplains to Jennifer how to control her transformations, since like his they are based on her anger or fear response. Jennifer retorts that as a woman in the legal field, she has to constantly manage her anger and fear. In fact, this may be why Jennifer is able to control her transformations immediately. Bruce said to Steve Rogers in The Avengers that his secret was that he is "always angry." Any woman who has ever had to deal with dismissive male colleagues, catcalls from strangers, or any of the other common, constant indignities knows exactly what Bruce was talking about.
From the perspective of regular-old citizens of the Marvel Cinematic Universe, this makes She-Hulk the immediately superior Hulk hero. Unlike Bruce Banner, Jennifer Walters will never accidentally go on a rampage hurting people, wrecking city streets or "breaking Harlem." The real question, however, is how Jennifer is able to retain her original personality in She-Hulk form when it took Bruce Banner the better part of 15 years to do it.
Similar to how the gamma radiation poisoning affected Jennifer differently than Bruce, not much time is spent dwelling on "how" she retains her original personality. Bruce doesn't wail or moan that he had it so much harder; he's just delighted that he can move onto the more fun parts of Hulk training. Viewers are simply left to wonder, fantasize and debate as to why Jennifer is able to manifest her personality in She-Hulk form right away.
Perhaps because Bruce already did the science-y stuff to merge his Hulk half and his Banner half, Jennifer is the beneficiary of that work. It might be a non-issue because while both got their powers in an accident, Jen got radioactive blood and not just a blast of raw gamma radiation. (Though Professor Hulk does note that it should have been a "lethal" dose, just like the blast that got him.) It also might be something as simple as Jennifer being more emotionally healthy than Bruce. As she mentioned, being a woman means being an expert in anger management, so her Hulk half and Walters half just fit together better than her cousin's two sides.
Ultimately, She-Hulk: Attorney at Law confirms to already appreciative MCU fans that Jennifer Walters is superior to Bruce Banner by putting her right back into her old life. She gets to be a superhero and live her dream as a lawyer. All she has to do to really show up her cousin is beat-up Thanos and then save the entire universe.
Watch Jen Walters be the superior Hulk in the MCU when She-Hulk: Attorney at Law streams Thursdays on Disney+.