Sorry, I did not follow your meaning at first.
I agree - repeat (on hold down any button) has stopped working with silver apple remote and Kodi .. does it work on any version of Kodi with High Seirra ?
I will do some testing and update with results
EDIT:
16.1 - Apple remote repeat works
17.3 - Repeat does not work
17.6 - Repeat does not work
18 - Repeat does not work (kodi-20180605-23261e1a-master-x86)
Interestingly repeat does work after a delay in the top level of settings (array of icons). Just right arrow and wait. I also found it occasionally works elsewhere.
Debug:
here
Steps
Played a video - tried holding vol up/down a few times for a few seconds - repeat failed to work
Went to settings (first screen) - held down RIGHT button for a few seconds - repeat worked