Kopitar - 1st rd
Williams - 1st rd
Brown - 1st rd
Richards - 1st rd (took a 1st to get him)
Doughty - 1st rd
Carter - 1st rd (took a 1st to get him)
Those were the top 6 scorers going into the 2012 playoffs. Later round picks can obviously become star level players, but you need talent that shows through at an early age. Until the Kings start getting a couple of those kinds of players, and they may be set back another year because of Vilardi, it's going to be a while. From Brown to Doughty was 5 drafts. If Kupari is the Brown of this next generation, that's 2023 until they maybe get their Doughty. Then in 2009 they got the 5th pick, and that's 2024, so 6 drafts.
Although to be fair, between Brown and Doughty, they completely missed on 2 picks. If you don't miss, the number of rebuilding years might not be too bad, but you can't miss.