When creating SharePoint site columns and adding them to content types programmatically, we normally commit out changes by calling the update function in the syntax:-
Did you know that on the site content type you are updating, this function does not tick ‘Yes’ on the “Update all content types inheriting from this type?” but leaves it tick as ‘No’ as seen below, did you know? I didn’t.
So now for this option to be tick ‘Yes’, you would have to call the same function, but this time pass the boolean as follows:-
Please take note that I would have already declared ‘ContentType’ as SPContentType of course.