I have tried a few times to move back to feature phones, but it has gotten exceedingly difficult nowadays. What I currently think is missing is a containerization/virtualization solution where you run something like lineageOS as a host, and then apps are run in their own virtualized containers. Ideally host can feed containers either actual data from the hardware (location etc) or some spoofed profile/gps/sensor data, say, profile 1 for some apps: single mom living in small midwest city, profile 2 for some other apps: megarich guy globetrotting the worlds famous places etc. All while the actual phone is sitting on your table.