yes. Proof: I was on a 7/8 game winning streak with KDA in every game above 3.0.
I was put on a team with a 1st time Cassiopeia top that had a 5 game losing streak, a Xerath with 70% win rate who got stomped by a 1st time Orianna autofill mid (most played was support and ADC, then top, never played more than 6 games of mid this season), a MF that lost 9/10 previous games and threw a level 1 double kill into the gutter and a low win rate Braum that lost 5/7 previous games that refused to leash.
In plat elo everyone played like bronzies. This MF was supposedly "plat 4" yet does not buy a single pink ward, and gets solo killed by enemy bot lane despite having a level 1 double kill. The "plat 4" Cassiopeia 1st time top has a level 1 kill yet still gets destroyed by Riven (also does not buy pink wards). Xerath complains about being camped - no pink wards, of course. And even in these horrid conditions, I maintain KDA of 5.0.