It's historical. IIRC WhatsApp started out as an app for people to post those statuses as they travel, to let know their family and friends their whereabouts. To that effect, the founder of Whatsapp was first talking about it in online frequent flyer forums such as FlyerTalk that he was already a member of. Chat came later.

Quick Google search would suggest that the current status feature was only added in 2017.

rolleiflex is referring to the text status along with profile picture. The other new Status feature was added in 2017 when Facebook went crazy adding Snapchat Story like features to all their apps (Facebook, Messenger, Instagram, Whatsapp)