With the release of the MacBook Pro in 2016 Apple also decided that the classic startup chime from 1999 had to go. If you are dealing with grief due to this know that it is possible to restore it again! You just have to do some typing in the terminal.
Open up Terminal on your Mac (search for it if you dont find it).
Type this in the Terminal to enable the boot chime.
sudo nvram BootAudio=%01
Type this in the Terminal to disable the boot chime.
sudo nvram BootAudio=%00
You have to enter your system password when you do this.