Well … apples and oranges are both fruit but offer different experiences. Neither good nor bad, just different.
Similarly, a 63mm conical and an 83mm flat, each with quite different burr geometry, offer different experiences.
That pretty much sums up why we have different burrs.
They can both do everything, and they each do some things better than the other.
A 63mm Mazzer Kony conical is my pick for a double ristretto pulled with a La San Marco lever and a medium roasted Kenyan Lena AA at 93 degrees. That’s a match made in heaven. For me.
An 83mm Gorilla Gear DLC flat is going to give me what I want with a light roasted high altitude Yemi bean using Rao’s Blooming profile and 96 degrees on the Decent.
Those two experiences are a world apart, as far apart as an apple and an orange.
But I think that within the great Conical vs Flat debate, there are other variables that have to be factored in, in order to reach any meaningful (there is that word again) conclusions, and the most impactful of those variables are the bean and roast depth.