Dax Milne and Gunner Romney have accounted for 73% of the WR yards. The remaining 27% is split between 6 players. Milne and Romney are the clear cut top 2 and Zach is feeding them the ball.
Last season, the top 2 receivers (Simon and Shumway) accounted for only 48.6% of the WR yards. The next 3 receivers accounted for another 48.5% of yards.
The last time BYU had a receiver eclipse ~800 yards in a season was in 2014 (Leslie and Mathews). It's been by committee ever since.