B&N's 'competitive advantage' today is not experienced staff. I can't ever recall an employee up-selling significant amounts of merchandise, or having a customer relationship that might move a needle.
Like Sears, it has real estate and a terrible retail position. If you treat the stores like mini-warehouses, with Amazon-warehouse-worker-hours, it might work. My guess is that failing to staff-up for the holidays was, seen charitably, a way to get the full-timers through the holidays.
I don't think so. Outside of the airport that's not useful to anyone. At that rate you can just go to the section where they have bestsellers at Costco or Walmart. A bookstore with no selection is practically pointless.
Target has more merchandise than B&N, but there's no career employee on the floor to suggest that you might like Mossimo if you bought Merona.
There are also various regional retailers.
The last book I bought at B&N wasn't so long ago. They pulled it off the shelf and had it waiting for me when I arrived. I appreciated being able to preview it to decide it was worth buying.
I don't have a local B&N anymore, but a local independent book shop is pretty good. They've ordered new books for me to preview too.
I haven't bought a book at a retail outlet in probably 10 years. There's just nothing about the retail experience at B&N that's even worth the effort to drive there and park. It's not salvageable.