Hardened kernel is now supporting 6.7.6 now, but hardened-kernel Kicksecure .deb package is still at 4.x, can we make it up-to-date?
No.
At time of writing, not in development. No maintainer available. Would
be a ton of more work. Was never available for users. Not realistic in
the mid term future. Very long term perhaps but not need to ask for
updates. If something reliable was available it would be made available
by default with no user action required.
Are you the only one developer of this project?
There are volunteers, contributors. See:
But nobody is working on that.
I see some names working in kernel hardening?
Nobody working on that.
Kernel hardening is security-misc: Enhance Miscellaneous Security Settings.
hardened-kernel is about recompilation.