Early Arduino were all AVR 8-bit, at the time it was already on the way out. There were no shifts in industry to those chips.

People who got Arduino, either:

- blinked some LEDs and forgotten about it

- switched to esp32 and/or stm32

  - esp32 and esp8266 move is funny because people started buying esp8266 to add Wi-Fi to their arduinos and then realized that they can just throw away arduino all together.

 - switched to cheap clones that offer more
  
   - quick connect for that not only want to blink LEDs, but also have some cool graphs to look at (like temperature and humidity)

   - boards that specifically designed for their use case (i.e. battery and eInk connectors and circuitry required)

Arduino is inconsequential to industry as whole or even to hobbyist using it.