Is Garmin Express needed for the latest Wi-Fi capable devices?

I am having issues with Garmin Express saying I cannot sync my data because my device is not the active tracker, although it is indeed set to be the active tracker, and no other devices exist in my Garmin Connect website, or here: https://my.garmin.com/mygarmin/customers/myUnits.htm

So I was wondering... do I really need Garmin Express, or can my Fenix 5S Plus download firmware updates and map updates without Garmin Express?