Should I turn on Firmware Password the moment I receive my 2018 MBP?

[ISKOTB]

Nowadays anything with a user/password is crackable. If a laptop got stolen they can simply mail in to get that EFI removed.
Just watch out for your stuff.

 

[_Kiki_]

It stops someone from booting your Mac to any drive other than the current drive set in the Startup Disk panel. So if someone steals your Mac and tries to boot to recovery or another drive to hack or reset your Mac, they will be unable to do so.

If you have the firmware password and FileVault both turned on, the thief has essentially stolen a MacBook that is worthless to them.

not really, firmware password can be removed, but I can't tell publicly about this method on the forum