the bit where he complains about the two useEffects, that's indeed disgusting but that's because whoever wrote it is an idiot, that should be useMemo, and then it would be obvious to read etc.

Given that of the three dependency items between the two useEffects, only one is actually used in the useEffect where it is listed as a dependency, there are deeper problems than using useEffect where they should probably be using useMemo there, but, yeah, it definitely looks like code written by someone clueless about React basics.