The TCL Chicago will never come to market, but the company has shown the device off anyway. The clamshell foldable closes flush, has a reasonably large cover screen and a larger battery than the Galaxy Z Flip 3 and Moto Razr 5G.
https://www.notebookcheck.net/TCL-admits-to-developing-and-cancelling-a-clamshell-foldable-that-would-have-undercut-the-Galaxy-Z-Flip-series.560672.0.html
I would probably use one of these when they start to hit $200 or less. Got that flip phone nostalgia.