If I put a SD card with ex. Alpine Linux into a pi, it'll boot into Alpine Linux. If I put a SD card with Alpine Linux into a Pinebook Pro, it'll boot into... Manjaro.
EDIT: Actually I guess the Pi 4 added an onboard flash chip with an early bootloader, but I can't figure out if it impacts the boot order or changes how hard SD boot is: https://www.raspberrypi.com/documentation/computers/raspberr...