From what I read on the ntpsec website, it's essentially a clean up of the ntp codebase as the latter has accumulated a lot of cruft over the years.

OpenBSD developed OpenNTPD precisely because of the state of the ntp codebase. Why not start off this, and add the features that are missing ?

Another question: why is the Linux Foundation funding both ntpsec and ntimed ?

My previous question also applies to ntimed, but that's not for you to answer :).