3 annotated examples
Design executive portfolios
At the executive level the audience changes. Boards, CEOs and search firms are not going to read a case study. They want to know what you believe about running design and whether you can say it clearly.
So the executive sites here are mostly writing: a newsletter with a bio attached, a twenty-year archive of essays, a one-sentence positioning about systems and operating models rather than products. When nothing current can be shown, the job itself becomes the content, written while doing it.
The risk at this altitude is assuming the reader already knows who you are. The best ones keep a line of career context next to the thesis.
3 portfolios

ExecutiveEnterprise
Jehad Affoneh
Chief Design Officer at Toast
A working CDO's site is a newsletter with a bio attached.

ExecutiveBig Tech
Mike Davidson
Design Executive leading the largest design team at Microsoft AI
An executive's site that is entirely essays, and the essays are the argument.

ExecutiveIndependent
Rachel Kobe
Chief Design Executive
The C-suite version: a thesis, a writing practice, an advisory offer.