A terrible career move. As other commenter said, if there wasn't a pay cut, is because of the company charity. Now she has to be not only a good coder but a great one, (and in a tech stack she didn't had used already). Otherwise, a year from now, they might not feel so charitable, and the story will be "from director of design to fired IC". A friend of mine made a similar mistake once, believing the BS of the "parall…
It is a risky move and not one I would recommend to anyone - but it is one I‘ve done myself (incl. pay cut) to get the experience to boost my career. Also keep in mind that careers span decades and while specialization is sought the landscape does shift (sometimes quickly) and diversity of skills can provide a degree of robustness.
And yes, the career track slides are not a foundation on which to base decisions.