I disagree. For a toothbrush, the chips are a problem. If nothing else, manufacturing chips is very bad for the environment. We shouldn't be putting them in things that don't need them.
If we were talking about the climate problem, you would be right. But your comment is a goal shifting, because I replied to the problem of abuse of the firmware in the chips. Abuse can't happen with free software.
I don't see a problem really. What's wrong with being able to fine tune, e.g., how strong the vibration is? Maybe my teeth are more sensitive than usual. Or between 'sensitive' and 'normal'.
