I think it’s nearly as big as the market for smartphones in general. I think the vast majority of smartphones sold in 2035 will be folding or flip phones.
Only because phone manufacturers think we want larger and larger phones. No flip phone is a half phone that unfolds into a normal size phone, not it's a phone that unfolds into a tablet.
Strange how every post on reddit I've seen about the new iPhone foldable is about the screen cracking within hours of purchase and the display moving to the wrong side when folded. But ok, sure, apple did great, ig