No. Per the bike radar test, the 2.8” Butcher tire (measured width 2.65”) vs the 2.3” Butcher tire.
There aren’t a lot of tests that I can find measuring performance of different tire widths. The one linked is the best I’ve found, but it’s 5-6 yrs old at this point.
The reason I resurrected this thread is based on my experience yesterday riding 2.6” tires on a chunky technical trail. They felt better - less chatter, better grip - and maybe faster (based on my non-scientific segment time comparison) vs my narrower tires.
Keep in mind that wider tires and lower pressures (than “traditional”) have been shown to be faster for road and gravel, and both disciplines have moved to wider tires over the past few years.
And MTB is already heading in this direction with 2.4” tires on 30mm rims becoming standard for XC. If XC bikes were designed to fit wider than 2.4”, might we see even wider tires on the more technical, rough trails?