The Los Angeles Rams lost on Sunday and fell to 1-3 on the season. The San Francisco 49ers won their game to rise to 2-2 while the Arizona Cardinals lost and are now 1-3, but they hold the tie breaker over LA. The Seattle Seahawks play on Monday and will either be 3-1 or 4-1 (unless there is a tie) after the game, so Seattle is safely in first place at this time.
There are still 13 games left for Sean McVay and the rest to figure this out, but they are behind right now and there is no denying that.