One way to keep relatively current is to follow Debian testing rather than Debian stable (currently Trixie). The stable release is updated infrequently but the testing release is continually updated as packages are introduced into unstable and get promoted to testing. FreedomBox builds images for both Debian stable and testing. The downside is that testing is less stable than stable.
At this point, being on Debian testing wouldn’t get you to Wordpress 6.8.2 since stable, testing, and unstable are currently all at 6.8.1. However, it’s likely that the Wordpress package will get updated to 6.8.2 at some point and end up in testing, at which point FreedomBox instances on testing will get updated.
You might want to take a look “20.1. When Will I Get the Latest Features?” in the Software Updates section of the manual or this forum post on switching to the testing release.
I can’t speak to upgrading Wordpress outside the Debian/FreedomBox process.