I disagree, I think for the average hobbyist Arduino is an abstraction of "thing that can talk to sensors and actuate motors." You're right of course that RPi (excl pico) is very different from Arduino, but for the hobbyist it makes no difference if the processor on the Arduino is an Atmel or an ARM.

> but for the hobbyist it makes no difference if the processor on the Arduino is an Atmel or an ARM.

I don't think anyone was arguing they cared about Atmel vs ARM. In fact, the point of Arduino is to make that not even something a user would need to know.

The argument is Linux vs Bare metal Arduino are vastly different user experiences and complexities.