Linux

if i am not wrong, boot process on non x86-64 is not standardised (no obivous uefi independent of os or setup). this genuinely limits the distros one can find, and mostly first party support is all you get. when first party does linux (raspberry pi or other sbcs), it is fine, and often their boot can be "used" by other third party distros (assuming license allows that). if first party does not, there is no way to get work done. something like android - if you get first party unlockable boot lock, you can hope for custom roms, without that, its playing darts where board is invisible. with apple mac, enough people had dart boards that random trial (and recovery processes) allowed them to get in. with qualcomm stuff, there is some first party support (and some second party support from nvidia who use qualcomm cpu for their servers) but qualcomm graphics is still a issue (first party support is very slow) and not enough third party interest (not enough people have qualcomm laptops for dartboards)