Short answer: it depends.
Longer answer:
https://www.runnersworld.com/nutriti...will-you-burn/
Quote:
Lastly the calculations only apply to walkers doing an 18:36 pace and runners doing a 10:00 pace. Running faster or slower than 10:00 pace doesn’t make much difference in your calorie-burn per mile. (But has a major impact on your burn per minute.)
Walking is a different kind of animal. Increases in walking speed dramatically raise calorie burn per mile as well as per minute.*Indeed, at about 12:30 per mile, walking hits a point where it burns about the same calories/mile as running. Walk faster than 12:30 and you will burn more calories/mile than running at 10:00 pace.
That said, ultimately this is all neckbearding, especially in jmakin's situation; the best workout is the one you're motivated to perform consistently. If you like to walk, walk. If you eventually feel motivated to track your pace and try to improve, great, but just consistently walking, eating at a deficit, and cutting out most of the booze will get you to where you want to be quicker than you'd expect.