They were director of design! I am not part of that company so it’s possible that director is a joke there but in most companies that’s the highest level prior to the c suite/owners (public company/professional services firms). That would mean she likely had immense autonomy and a large group of direct reports whom themselves had teams of direct reports. Going from that to “just a coder” ie one team member of one team responsible for only their contributions to their current projects.

In nearly every organization that would be a huge demotion WITH a huge pay cut. In this instance because coders are paid so much more than most other professions it’s possible it was a lateral move or even a pay raise! But no question as far as responsibility for the direction of the organization it’s a huge demotion.