Obsolete is premature but it is certainly a diminishing market.  

I have never bought a handheld GPS device until this year...It's a Garmin InReach Mini and my principle reason for having is not GPS as such but Satellite Messaging.  However that does combine with position tracking.  In addition it can receive weather reports.  These services require a subscription.   It also provides a backup GPS position and local tracking.  It is not a mapping device except in combination with a smart phone.  While it is standalone for messaging it is fairly inconvenient to use for custom messages without using your smart phone.  However it can be done...with some planning you can use the quick messages and preset messages for most purposes.

I have otherwise always used paper maps and prefer them in general as my principle mapping "device".   I now use the phone as a backup and extension to paper maps.  However paper maps are not always practical and I do not agree that paper maps are mandatory .

As I said in that other thread,  I think there is still a strong case for a device that combines the satellite messaging with on device mapping for redundancy.  Smart phones are not very rugged. Electronics in general requires management and a "system" to keep things working for long enough in the back country.   If you go all electronic, you should seriously consider having a redundant system.