The focus here is sugar placed on the body to treat wounds. Although, even in the body sugar is not so bad.

The Healing Power Of Sugar, BBC, 30 March 2018

To treat a wound with sugar, all you do, Murandu says, is pour the sugar on the wound and apply a bandage on top. The granules soak up any moisture that allows bacteria to thrive. Without the bacteria, the wound heals more quickly.
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A growing collection of case studies from around the world has supported Murandu’s findings, including examples of successful sugar treatments on wounds containing bacteria resistant to antibiotics.
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But a great deal of medical research is funded by pharmaceutical companies. And these companies, he points out, have little to gain from paying for research into something they can’t patent.

Is it useful on people with diabetes? Yes:

One question he had to answer during his research was whether sugar could be used on diabetic patients, who commonly have leg and foot ulcers.

He found that it worked for diabetics without sending their glucose levels soaring. “Sugar is sucrose – you need the enzyme sucrase to convert that into glucose,” he says. As sucrase is found within the body, it is only when the sugar is absorbed that it is converted. Applying it to the outside of the wound isn’t going to affect it in the same way.

Sugar, as well as honey, is also useful on pet’s wounds.