This is a known fallacy called false dichotomy
I fully agree. Iād also like to add that there is also benefit in doing Z2 in a fatigued and reduced carbohydrate available state. Theoretically youād engage even more muscle fibers due to loadsharing.
So thereās probably pros and cons for both approaches and in the end the most important thing is increased volume, if this YOUR way to achieve, then itās the best way (for you).
100% yes, there is benefit. Zoom out and look at the big picture of how much volume you would add over the course of the year by adding an average of 30 min to all these workouts. Thatās going to add up to a huge amount and really help with year over year improvements.