It looks like an iOS13 device in dark mode will render the spinner datepicker's text as white (instead of black text when the device is in light mode). Since the wrapper's backgroundColor style is set to white, the text inside of the Datepicker modal will be invisible on an iOS device set to dark mode.
A quick fix/workaround is to set the wrapper background to 'gray' instead of 'background' here: https://github.com/RizeFinance/compliance-demo-ui/blob/4599730236e783fb307bc80cd9e3c62b8d9027d7/components/DatePickerInput.tsx#L25
because white or black text will show up visibly on the gray background.
I noticed that the Themed.tsx component does use the useColorScheme hook - but I guess the issue is that in Colors.ts it uses the same colors (including background being white) for both light and dark mode.