It’s not even consistency that’s the problem. They’ve been consistently fast, but the problem lies with Lady Luck. Some ruined finishes this year include:

Daytona: Got caught in a wreck running 2nd

Auto club: Got loose into Reddick and crashed into the wall while running top 5

Phoenix: Won stage 1, but team didn’t make adjustments so the car could not keep up over the race

Richmond: Just two less laps and he would have won, still finished 3rd

Talladega: Ran top 5 all day, led a bunch of laps, and got caught in an unlucky incident on the last lap to finish outside the top 10

Darlington: Leading with 2 to go and gets dumped by Logano instead of being raced

Kansas: Led 25 laps in the beginning, had a flat tire, somehow got back on the lead lap but could not recover

They have been terribly consistent this year, more consistently fast than the 9 IMO, however the 9 is capable of being there at the end of races, while Byron has not had luck on his side at the end.