You were right to bring up the Just War Theory because this is a great example of something that is recognized as a discipline. It is not a hardline teaching, it is something the Church has brought up as a prudential matter — this is the case for the death penalty.
The earlier popes who supported the death penalty were not in error and their support for it was totally right.
As things like security in prisons have evolved, the need for the death penalty began to reduce. Pope Francis made a judgment (albeit a fallible one) that we’re at a point where it is no longer needed. JPII before him said we were practically already there.
This is why it is not an intrinsic evil — it is merely recognized as inadmissible.
That said, from my understanding, this also means Catholics who still support the death penalty may still do so, it’s just that the Catechism reflex a specific position, but it is not doctrinal. This is why it was worded in this way.
I do understand my fellow traditionalists concerns with it, and I think the timing was odd, but it still makes sense to me.
I’d check out Trent Horn’s podcast on this subject. It was very well explained.