No. I finished Breaking Bad same year it ended and just recently watched El Camino. I was able to follow along no problem.
As long as you watched the last 2 seasons of Breaking Bad, you'll be fine. There are a few little things that come up in El Camino that you won't understand if you haven't finished the Breaking Bad series.
There is no reference to Saul ...
If Jack's gang wasn't wiped out, how would Skyler's safety be assured?
There were only two possible outcomes: Either the plan succeeds and Jack's gang is wiped out, or the plan fails and Walt dies (or is taken prisoner like Jesse).
If Jack's gang is wiped out, it's clear why the threat ceases.
If Walt dies, the threat will also cease as there's no reason ...