Ok, that makes sense. Thanks for the details then. I haven't encountered this personally but am aware of the workflow. Now I understand why >1200 is so much for this scenario, I've gone to 100 but nothing of that scale. Even in Survey123 there are no ways to alphabetize these lists that I am aware of. There may be a way to code it so it shows alphabetically, but I digress from my knowledge and would defer to the other ESRI contributors.
One solution I can think of it having a preset feature service where your field and dropdown automatically draws from the list rather than manually entering them, however that sounds about what you are already doing so I don't see any benefit specifically.
Jansen Lyons - Records and GIS Section - Public Works - City of Rio Rancho, NM