You should probably mention that the vendors at least make an attempt at a 'standard' for their platforms. Whether or not developers follow it, is up for debate

You should probably mention that the vendors at least make an attempt at a 'standard' for their platforms. Whether or not developers follow it, is up for debate. https://developer.apple.com/design/ https://developer.apple.com/design/ https://material.google.com/ https://material.google.com/ https://developer.microsoft.com/en-us/windows/design https://developer.microsoft.com/en-us/windows/design