The figure for calories consumed when walking is excess calories consumed (compared to sitting still)

Are you sure? It doesn't say that.

I am sure. Think about it for a minute and you'll see why

I don't. Could you explain what you mean?

Here's what I found: the formula given in the article is "calories burned = BMR x METs/24 x hour"

But the METs for lying quietly is 1. The author certainly forgot to subtract 1 from METs in that equation, and could easily have also forgotten to do so when calculating the given numbers.

https://pacompendium.com/inactivity/

It just wouldn't make any sense to tell people "you burn X calories when walking/running/whatever for an hour" if they had to subtract their base metabolic rate from the number.

I agree it should state the excess calories burned. I think the author probably misunderstood the formula.