You asked if you were missing something, and you were. You thought Christmas Eve was a federal holiday. If you choose to read more into it anyway, that’s your prerogative, but I see nothing weird about Trump giving federal people a commonly-celebrated holiday off.
Christmas Eve was not a federal holiday.
https://www.doi.gov/messaging/president-trump-grants-december-24-federal-holiday
https://www.govexec.com/pay-benefits/2019/12/surprise-move-trump-gives-federal-employees-christmas-eve/161974/
You asked if you were missing something, and you were. You thought Christmas Eve was a federal holiday. If you choose to read more into it anyway, that’s your prerogative, but I see nothing weird about Trump giving federal people a commonly-celebrated holiday off.