Maybe you're luckier with English, but having recently tested a Uniherz Titan Pocket with physical keyboard, I just realized how my "past memories" left aside many details: typing accents and special symbols is slow; the absence of auto-complete on some long words is noticeable; the lack of emojis, the lack of a numeric keypad, having 3 or 4 modifier keys (to handle case, numbers, secondary functions, etc), all of these things I got so used to in virtual keyboards... I actually missed them more than I expected. This, plus the virtually unusable screen due to the lack of remaining real estate, made me rethink my memories.
Granted, part of if is Android's fault, and part is the keyboard itself (the modifier keys in particular), but overall, it made me feel better using a touchscreen keyboard. I no longer have rose-tinted memories that make me complain so much about on-screen keyboards.
Okay, sure, typing accents with this type of keyboard may be worse than what we currently have on smartphones. But as I mostly write English this would not be a huge problem to me, otherwise in German there are only äöü/ÄÖÜ and ß/ẞ which don't get used that much, but have extra keys on the German keyboard layout (I don't expect this to be the case on a keyboard phone). Or can be replaced with ae,oe,ue and ss respectively.
Auto-complete/-correction is something that I don't use often, but this doesn't need to be missing from a keyboard phone, as this could be added on the software side.
Emojis are also something that I don't use often, but I get it that people may miss this, but this could also be added on the software side.
I have something similar to the BlackBerry Key2 in mind [0]. Haven't tried it myself, as I just learned about this through the comments. But the keyboard layout on the Key2 looks way better than the Unihertz, and the numerical keys are even in the same layout as a numeric keypad.
I may as well have too many rose-tinted memories of this era, but I don't think that the things you mentioned would be showstoppers for me, but I definitely can understand that these will be blockers for other people.
Granted, part of if is Android's fault, and part is the keyboard itself (the modifier keys in particular), but overall, it made me feel better using a touchscreen keyboard. I no longer have rose-tinted memories that make me complain so much about on-screen keyboards.