Comment by rainingmonkey

The FxTec Pro 1 is the closest I've found these days; it has a slied-out keyboard and an unlocked bootloader so you can run LineageOS or Ubuntu Touch (PMOS support seems spotty).

The keyboard isn't as nice as those on phones from ~2010; it's a bit too big for the thumbs to really fly and sliding it in & out is not as effortless as it should be, but nless you count Unihertz's blackberry-likes, there's really nothing else around that comes close!