Unfortunately, Doctor Who used Chris Chibnall's Timeless Child arc to define Jodie Whittaker's time as the Doctor. Whittaker will go down in history as the first female Doctor — hopefully the first of many. Although this was initially controversial, her performance has won over critics; even Seventh Doctor Sylvester McCoy initially complained about the casting, but came to admit his concerns were "stupid sexism." Doctor Who: Flux easily featured Whittaker's best performance as the Doctor, with a new sense of kinetic energy to her portrayal.
And yet, for all that's the case, the controversy will continue. The casting backlash has been superseded by intense debate over current showrunner Chris Chibnall's Timeless Child retcon, which rewrote Doctor Who's history and lore. It revealed the Doctor is in fact the Timeless Child, a being from another universe who became the base genetic code for the Time Lord race. Unfortunately, it's now becoming clear this story defines the Whittaker era.
The core problem is that Chibnall clearly intends the Timeless Child to define his run as showrunner — and he and Whittaker are a package deal, with both signing on for three seasons (and wrapping up their runs in three specials that will release in 2022). The Timeless Child was signposted in Doctor Who season 12, the retcon was unveiled in season 13, and — according to Chibnall and Whittaker's own breakdown of Doctor Who: Flux — season 13 spun out of it. That breakdown further highlighted elements that will clearly be explored in the 2022 Doctor Who specials. It means Whittaker's entire tenure, as well as Chibnall's, is all about the Timeless Child.
There's nothing new to the idea of Doctor Who seasons having single overarching narratives; it's been standard since Russell T. Davies relaunched the show in 2005. But Christopher Eccleston is the only Doctor to be associated with just the one narrative, simply because he only played the Doctor for one season. This means the Whittaker era depends entirely on the effectiveness of the Doctor's Timeless Child retcon; if viewers ultimately aren't satisfied with the story arc, then Whittaker's entire run is damaged as a result. In strategic terms, the decision to associate an incarnation of the Doctor with one story is a high-risk move.
At the moment, things don't look good. The Timeless Child retcon has divided the fanbase; although Doctor Who: Flux was a marked improvement, it was still flawed, and the 2022 specials were filmed at the same time, meaning it's impossible to course-correct at all. Still, even if the arc doesn't wrap up effectively, there is hope for Whittaker; she'll surely be welcome in future multi-Doctor stories, and hopefully, she'll wind up reprising the role of the Doctor in Big Finish audio-dramas as well. It's just a shame her actual time starring in Doctor Who will be defined so strongly by the Timeless Child, potentially overshadowing Whittaker herself.