FreeBSD ports are more up to date. Debian packages are famously out of date - their claim to fame is stability not staying up to date. Arch is a better comparison here if you care about this you would be asking about Arch not Debian: that you are asking about Debian implies you want this out of date.

The other major difference is FreeBSD ports lets you chose the build options - the defaults are normally good, but if you don't like how Debian (Arch...) choose to build your packages you are not stuck. Ports even mixes with binary packages so you can choose the defaults for some things and build others yourself and the system will track everything and when things need to be updated. This is something you rarely need, but when you do FreeBSD soundly beats everyone else just because the effort is so much less (again though, most people never need this in the first place - and Debian has pushed less need of this on applications which is a good thing)