For flip phones the payoff is that its small.

We've been asking for a small phone for so long now

And then now we have one. But its too costly. I'm waiting for the cost to come down

For foldable phones the factor is that you have a phone and a small tab all in one.

I had a flip phone and I got it for this reason, but it honestly just sucked. The outer screens are too small to be useful, or in the case of Samsung, just don't have the right feature set to be useful. That means the phone ends up just being a full size smartphone with more steps to be able to use it.