This doesn’t surprise me. Friends and family with 2021+ ecoboost lariats etc only run 93 octane now after playing around with 87 and 91. They say it just behaves/performs better and gets better fuel econ.
When I purchased the Lariat the salesperson told me 87 is all that is required and as previously indicated, the owner’s manual articulated the same. That and towing capacity was a huge selling point. It wasn’t until I spoke to someone whom works at Ford when I learned differently. Just like towing capacity, it’s all about marketing. Luckily, I discovered the truth before the Lariat hit 1900 miles. I have always filled the Raptor with 91 or better. On a side note, I was at a party last night and spoke to a big shot that works at Kraft foods. To make a very long story short, he confirmed that “store brands” , although made by Kraft, are actually different, which is the reason they are typically cheaper. He told me the cheaper items “often” contain ingredients outsourced from countries like China. Whereas, most of the ingredients contained inside Kraft label products are produced in the US, Mexico and sometimes Europe. That made me think about OTC drugs and generic prescription medications. Regardless, the Lariat performs much better on 91 or better……very noticeable!