I'm familiar with that phrase that is trendy among college-students.

But it fails to realize most attacks are telnet and ssh attacks, so if you change your port, the bot will move onto the next IP address.

DSM has been targeted in the past as well, which is why Security Advisor recommends you to change the default port.

Don't forget how many computers are on the internet and how easy it is to find targets with known vulnerabilities. Don't let yourself and your NAS get noticed in the first place...and you won't be subjected to a more sophisticated Targeted attack.