In a software project, it is not uncommon to have long running performance/test jobs, which cannot be split for whatever reason. In those cases it is desired to have the latest build tested and not all from the oldest to the newest. Eg the newest build is being tested last.
For declarative Pipelines it could be a skip phase if queue is "too" long.
For freestyle the queue on the build could be "managed" to cancel X number of jobs depending on time in queue or number of builds in queue.
I have done a "hack" for freestyle where I cancel the queue on downstream jobs before I set "myself" in queue and then become the next being executed after current build is done. Cancel downstream queue
I have looked at the Git SCM plugin as it has the combine sha1's, but will have the upstream/downstream relation to the first triggered in queue and not the last, but it also makes it a Git plugin and not a generic.