apt - Is there 2 options to install mysql? and Have Ubuntu decided to maintain up to date mysql with the latest version in his 16.04 Xenial repositories?

I have installed mysql from the official ubuntu repository, runing this commands.

sudo apt install mysql-server

Even you can install mysql-workbench. And this is the version, and yes it is the latest.

peter@peter-desktop:~$ mysql --version
mysql  Ver 14.14 Distrib 5.7.20, for Linux (x86_64) using  EditLine wrapper

In the mysql documentation you can install it by installing his mysql apt repositories.

Then, It is a matter of personal preferences or is there some other matter?
If it exist, please share with us the details.

I ask this, because this surprises me that mysql has being up to date in ubuntu 16.04 LTS xenial repositories.