I would argue that depends on what you want out of a camera, David.
For example, sports photographers won t even glance at the R5 when something like the A1 exists because of A) it s rolling shutter with high speed sports, B) using a EVF that has zero blackout (a really beneficial experience) and C) FPS. The A1 is also better at shooting with a silent shutter under artificial lighting than the R5 because of the anti-flicker modes and the automatic adjustments to shutter speed to account for flicker for lights that do not operate at 50 or 60hz. For a lot of similar reasons, I think a lot of photojournalists would also go with the Sony as well. I am, at least, because the things I mentioned are a factor for my photography and can be a massive aid to help you while you re working.