Well, Apple is still trying to hang on to the iPhone Air, and according to various reports it has sold only about half the total units that the mini sold. And Air sales have cratered to virtually zero.
Folding phones will likely be an even smaller market.
I don't think the problem is that there isn't a dedicated percentage of people who would buy smaller phones like the mini, or that the sales couldn't be profitable. The problem is that the screen size to battery volume ratio is or least was particularly bad for the mini. (The Air has this problem too.) I'd love to see them try again with modern hardware. I wouldn't use one personally, but know many people who would in a flash.
Folding phones will likely be an even smaller market.
I don't think the problem is that there isn't a dedicated percentage of people who would buy smaller phones like the mini, or that the sales couldn't be profitable. The problem is that the screen size to battery volume ratio is or least was particularly bad for the mini. (The Air has this problem too.) I'd love to see them try again with modern hardware. I wouldn't use one personally, but know many people who would in a flash.