The problem is, Cass can't communicate in any other way. Not really, and that's the whole point of this scene - that Bruce was the only one who could get through to her or help her at all. Cass was stressed out, flipping out, feeling hurt and rejected and unsure of her place, and she could not express that except by trying to beat the shit out of Bruce (or, earlier, by beating the shit out of the Soul users). She felt like Babs was living vicariously through her, so... she beat up Batman. She didn't know how to resolve her feelings about Black Wind, so... she beat up Batman. She resented that Bruce didn't seem to trust her independence or focus, so... she beat up Batman.
Beating up Batman is, assuming that Batman also speaks that language and can understand her complaint and express his own perspective accordingly, is still a solution to exactly one of those problems. Him, and the characters around them, and the narrative itself, behaving as though it's a valid solution for all three, is actually furthering the emotional crippling of Cass, rather than alleviating it - she's being told she doesn't have to learn how to express herself to Babs better or develop any romantic or sexual self-awareness. She can just go beat up Batman. Which is great, right up until she actually wants to interact with anybody other than Bruce, or until Bruce goes and gets his ass Omega Sanctioned and leaves Cass with no coping strategy at all.
It's a reinforcement issue. You know the old expression "to a man with a hammer, every problem is a nail"? That's Cass. Her whole life, all she ever had was a hammer. Now that she's working with the Bats, people like Babs and Dick and Steph and even, as emotionally pathetic as he is, Bruce himself, she's got access to all these other tools, wrenches and screwdrivers and levels and tape measures and even, like, bizarre sawzall attachments that nobody in the universe has ever actually used. And the only one that Cass has any idea how to use is the hammer. The wrenches are scary and the screwdrivers are awkward and she's so fucking good with that hammer, faster and more accurate and efficient than anybody, what on earth is her motivation to ever even pick any of these weird new tools up? Well, for one thing, stop giving her nails. Stop letting her choose nails where screws are more appropriate. When she's fumbling with the level, stop handing her a hammer and sending her elsewhere, and sit down and help her figure out the damn level. Respecting that she'll always be best at hammering is not the same as being complicit in her refusal to ever learn to do anything else, which is what Bruce is all about throughout BATGIRL, and with the narrative's explicit approval here.