Despite holding her royal title for over a decade, many people still refer to the princess by her maiden name, “Middleton.”

PR expert Megan Boyle told Express.co.uk that the reason may come down to the “fairytale aspect” of Kate’s relationship with Prince William.
She explained: “Ultimately, we’ve always known Kate Middleton as Kate Middleton, and sometimes it’s hard to break the habit.
“She’s been a public figure for so long that royal fans feel a kind of parasocial bond with her. What makes her and William’s relationship so captivating is that it feels like a fairytale — from dating to engagement to marrying a real-life prince — almost like something that could happen to anyone.
“It’s a reminder of why people were drawn to her in the first place; she’s just a regular person, like the rest of us — who happened to become a princess.”

In addition, Boyle pointed out that social media and SEO — the process of boosting a website’s visibility on search engines — have a major influence.
“Of course, there’s also the internet playing a big part here,” she added. “From an SEO standpoint, the internet originally recognized Kate Middleton as Kate Middleton, and that’s still the term most people use when searching online. Since ‘kate middleton’ remains far more commonly searched than ‘princess catherine,’ media outlets are unlikely to risk losing their search rankings by switching the name.”
“From Kate Middleton to Duchess of Cambridge, to Princess of Wales, and eventually Queen — many media organizations would rather avoid SEO complications and continue using the name the British public has long associated with her.”