Why are the HP Prime and HP-35s so unpopular?

[Sylvain Cote]

I see these types of HP calculators:

• RPN handheld calculators
  → began as a electronic slide rules replacement and then evolved from that
  → integrated system
  → closed platform
  → no I/O (exception: HP-97S)
  → programmable: yes on some models, keystrokes programming
  → customer type (in order): engineer, financial, math & student
  
• RPN handheld computers (41)
  → integrated system
  → open-ended platform
  → full I/O (HP-IL, peripherals & modules)
  → programmable: yes, advanced keystrokes programming
  → customer type (in order): engineer, financial, math & student
  
• BASIC handheld computers (71/75)
  → integrated system
  → open-ended platform
  → full I/O (HP-IL, card reader & modules)
  → programmable: yes, higher level languages (BASIC & FORTH)
  → customer type (in order): engineer & math
  
• RPN over System RPL calculators
  → integrated system
  → closed platform
  → no I/O (exception: infra-red output on some models)
  → programmable: yes, solver, keystrokes programming
  → customer type (in order): student, math, engineer & financial
  
• AOS over System RPL calculators
  → alternative to RPN over System RPL calculators
  → integrated system
  → closed platform
  → no I/O (exception: infra-red output on some models)
  → programmable: yes, solver, keystrokes programming?
  → customer type (in order): student, math, financial & engineer
  
• RPL calculators
  → bring symbolic math to the calculator world
  → integrated system
  → open-ended platform
  → limited I/O (serial)
  → programmable: yes, higher level language
  → customer type (in order): student, math & engineer
  
• PPL calculators
  → applets based system
  → limited or no integration between apps
  → open-ended platform
  → programmable: yes, higher level language
  → customer type: student
  
• Rebranded AOS/RPN calculators
  → no comments
  
  

So, peoples needs and preferences will favor one type over the other.

In my case, when I ...

• need I/O → I use: 41, 71 & 75
• do embedded programming → I use: 16C, 41+module
• do scientific calculations → I use: 41, 32S, 25C, etc
• need symbolic math → I use: 48GX & 50G
  

I prefer integrated system (with full I/O when possible) over app based ones.

Sylvain