... Perhaps, but I believe Jim did a little retcon with Mab. In Changes I believe she explicitly says she is not cruel, but in the first books that is not the case.
Cruelty, of course, is relative.
The old joke goes "How do you punish a masochist? You
don't spank them."
The idea of "tough love" usually involves a cruel-seeming behavior.
etc.
And then, of course... we're talking
MAB, the Queen of Winter.
And, infamously, "winter is cruel" (it's a stock phrase).
Except it's not -- winter is impersonal; it just is what it is.
Mab can be absolutely horrific to somebody, without it being "cruel" on her part. Mab stands largely outside those human perspectives and moral judgements. "Simple human kindness" is another stock phrase; but it has nothing to do with Mab!
So, as
awful as early-book Mab was to Harry, she wasn't necessarily being "cruel" to him.
I'll also bring up my WAG that this is part of a multi-generational long-game plan of Mab's. Old as she is and Guardian of the Outer Gates, she knows about Starborn, and that the cycle has come round again. So, my WAG is that Mab laid plans -- likely beginning about a century ago -- to gain a Starborn as her Winter Knight, to combine the inherent Starborn Outsider-resistance to the Knight she has during this most-dangerous of times. She didn't just "stumble upon" Harry as a good candidate Knight -- she arranged for Margaret to learn about Starborn phenomenon, and to become "LaFey." She arranged for the Black Council to target Margaret as a Starbabe mother. She arranged for Malcolm's death, and Harry's vanishing into the orphanage system, and Justin to adopt him. Some (perhaps most or all) of this may have been executed by her Handmaiden, but the intent behind it all was Mab's.
So early-book Mab was very much in the late-stage part of her plan. And at that point, she was all about shaping Harry; at that point she needed (or at least
thought she needed) Harry to see her entirely as the
Evil Queen(tm), in fulfillment of
his expectations. What she was
actually doing was crafting her new Knight.
If she had thought it would work better for Harry to think she was "kind," Mab would have
acted in a kindly way, without
feeling any kindness towards Harry.