just curious if this was a case of people not interested/indifferent, or people not noticing...

Lack of visibility. I hadn't seen it.

Yeah figured.. and I guess with community ads it normally wouldn't matter, but this one effectively "expires" in a few days

Should we create a create a picture to advertise Puzzling on some selected SE sites ?

I think that HNQ that pop up are enough of a publicity to attract newcomers.

oh my... puzzling.stackexchange.com/q/38553/22184

This knight-moves tag shows potential.

I love this puzzle idea

I wouldn't say it's difficult, but it's very cool !