One image links to the 2015 article, "It's Ridiculous To Say Black Women's Natural Hair Is 'Unprofessional'!". The Guardian article on the Google results is from 2016.
Another image has the headline, "5 Reasons Natural Hair Should NOT be Viewed as Unprofessional - BGLH Marketplace" (2012).
Another: "What to Say When Someone Calls Your Hair Unprofessional".
Also, have you noticed how good and professional the black women in the Guardian's image search look? Most of them look like models with photos taken by professional photographers. Their hair is meticulously groomed and styled. This is not the type of photo an article would use to show "unprofessional hair". But it is the type of photo the above articles opted for.