check out r/dumbphones on reddit for examples. Most of the requests are "I want a dumbphone that does spotify, whatsapp, car naivgation, my banking apps, uber, podcasts, and facebook." Sometimes people point out that this is not a dumbphone, but they get shouted down.
In the typewriter days I believe it was brother who made many different models that each had their own case but all had the same hardware inside. The cheaper models simply didn't have the keys.
One could do a "smart" phone that has a predefined set of apps. I could see the advantage of having practical apps but not have the stuff that (depending on who you are) sucks the life out of you. Having [say] porn or gambling wherever you go might not be a good idea for some people.
I only got a smartphone in 2017 when it became impossible to do my job without the latest drama announcements on whatsapp. A few years before I had to get a dumb phone because it was getting to weird for people to not be able to contact me.
I've been doomscrolling nonsense ever since. People (as they should) make fun of me for not starting a conversation the way I use to.
I recently found myself unable to order food without a payment app.
It would be hilarious to purchase a phone providing a list of url's and a list of apps and having to pay for each. Changing the list should be expensive and take at least a month.
What they're really asking for is interoperability and openness with none of the cruft and dark patterns.
E.g., a music service that doesn't exploit artists or users, an interoperable messaging and calling system, a GPS mapping system, a way to spend and check their finances, RSS, and some way of interacting with their friends and family.
An e-ink device with a decent battery life could potentially do a lot of these things, but their processors are seldom great, and most apps aren't made with e-ink in mind, so render like crap. Android has also become quite bloated.
They might want the results of interoperability and openness, but what they ask for is a dumbphone that can run all their favorite apps. If you gave them a linux phone, they'd ask how to install their favorite apps. When they discover that you, essentially, can't, they'll throw it out and post another thread on r/dumbphones asking the same question.
That's why I think there's a market for phones like this 'Minimal Phone' even though to a techie it's just another android gadget. People ask for this device all the time. By the time they find out the walled garden still sucks in monochrome, someone will already have made a profit.
Many people want enough friction that the pleasure of using a smart phone is degraded but the practicality of maps, emails for work, etc remain. It's about resisting the intentionally addictive elements of hardware and software ui/ux and leaving the tool.
Then why would someone want a dumbphone if you're going to load G services on to it?