I am curious if there is a measurable benefit to the animal? If there is so much methane not being produced is it because the current diet is just so wrong for

I am curious if there is a measurable benefit to the animal? If there is so much methane not being produced is it because the current diet is just so wrong for the animal that the methane is the adverse reaction to it? Does cattle that is allowed to graze as it likes with no added foods producing the same amounts? Also, what is being produced if anything if the methane isn't? As before, is this beneficial or not to the animal.