I just finished reading the LotR series with my now-11 yo son (we started a few years ago) and there were definitely plenty of sections like this that I converted to more understandable terms and concepts on the fly. Sure my son may not have heard this exact line, but he definitely got the idea that ~~Shelob was old, bad, and Sauron had encouraged get 8 in exchange for a scary guard in the tunnels into Mordor~~ the fell beasts were scary.
Edit: apparently my son may or may not have gotten an entirely different version of the book told to him!
I really want to give him the entirely unwarranted benefit of the doubt that he's saying it won't matter in 4 years bc he won't be running (making the assumption he'll win this time and reach his term limit) but having watched the video I dunno, that "we'll have it fixed by then" sounds reeeeaaally ominous.