Samsung is a separate kettle of fish in that they make things difficult while keeping the bootloader technically unlocked. Things like a lack of fastboot option, or bespoke for Samsung security changes, and a whole mess of other things. Carriers do also impose addition restrictions for locked models.
From what I can tell, Odin should still work on US devices, but I don’t think that its been kept current with devices and Android versions. Most of what I’m seeing is support for Android 9.0 and later, which is pretty out of date at this point. That being said, it’s not something I’ve messed with much, so I’m happy to defer to someone else with more direct experience.