Google Sheets array formulas don't copy over correctly to an .xlsx format, so any and all arrayformula() will fail miserably when exported. I'm working on a fix, but there's a few array formulas that refuse to be changed into braces.
EDIT: Replacing arrayformula() with braces doesn't work either. There's a way to avoid it and make it work (which is not actually using arrays, which tbh is a sin), but it'll make it a headache to update the sheet.