My understanding is that the 1D series is considered "Pro" and the 5D series is considered "Prosumer".
I think that 1D and 5D series + EOS R are "Pro" cameras.
1D is the very fast, ultra rugged but heavy pro camera,
5D and EOS R are fast, rugged and reliable pro cameras with less weight.
Two EOS Rs and e.g. 15-30 or 24-70 + 70-200 2.8 might be a very good combo for a press
photograph/journalist (non-sports) because it should have a good balance between speed, IQ
and volume/weight. And there is enough room in a medium large backpack for
a small tripod, some audio equipment, notebook, some clothing, some emergency food
and 1...2 litres of water.