The remaining colors in GQColors.ts are related to Quadratic, which currently has:
public readonly color: Color | string;
Changing this to TColor or ProfileColorProperty will require changes to QuadraticIO, therefore changing the PhET-iO API. So unless there's a reason to convert the remaining colors to ProfileColorProperty, I recommend we leave them as is.
Partial support was added in the above commits.
The remaining colors in GQColors.ts are related to Quadratic, which currently has:
Changing this to TColor or ProfileColorProperty will require changes to QuadraticIO, therefore changing the PhET-iO API. So unless there's a reason to convert the remaining colors to ProfileColorProperty, I recommend we leave them as is.