I had a Seaforth kilt just like this years ago when I joined my first pipe band, (which was formed by ex-Seaforths). These kilts do indeed have box pleats.
I found that the box pleating didn't require any additional care compared to knife pleating. I did hand wash it once, and the 22oz blanket quality material was a challenge to press.

I most certainly agree that this is the worst case of badly pressed pleats I have seen. What a shame.