I came across that post while struggling my mind to have a better solution for our M0CUBE HMI project.
Since we decided to use Raspberry Pico almost in every M10CUBE design.
For many reasons using the PCF8574A chip idea was too old fashion and not power enough for our needs.
Thanks for the inspiration

M10CUBE project: https://hackaday.io/project/171770-m10cube
GitLAB : https://gitlab.com/m10cube/m10

Vasilis