I had a ZFold 4 for a good long while before switching to a Pixel with GrapheneOS (OP is right, it’s a legal requirement when joining lemmy). I can share my experience.

I really loved it but I also had very specific use cases. It was great for reading long-form content on the go and much more comfortable browsing websites, mostly those where they don’t have / use mobile-first design like old forums. It was also great for sharing content in person, like sharing a spreadsheet or slideshow in person became so much easier. Some edge cases were nice to have, like taking a conference call you could split screen at the crease and prop it up for a more laptop-like experience. Ultimately it did away with the tablet use case between my laptop and phone.

Downsides were definitely price, it’s like an $1800 phone, probably more now. I kept it for probably 4 years and still use it occasionally so I feel I’m getting my moneys worth. Not sure how the durability is these days, used to have issues with screens cracking even though mine is going strong. They redesigned it from 5+ in a way that it folds fully flat now and should extend screen life.

It really boils down to “is the screen real estate of two phones worth paying the price of two phones?” It has all the flagship features you’d expect, so you’re really buying the form factor.