I always read the product release statement to see if there are any other clues as to future products. One thing that I got out of the Canon Australia news release is that it seems more than ever to me that the R5 is indeed the replacement to the 5D, not just the mirrorless version. Here is the quote, talking about the 5 series rather than 5D...
"Our EOS 5-Series was developed fifteen years ago to make full-frame cameras accessible to consumers, not just professional shooters. Today, that purpose remains steadfast as we continue achieving the ‘impossible’ to deliver the hybrid needs of content creators who are demanding uncompromised performance to generate more still and motion visual content than ever before."
I may be reading too much into the statement (only time, or Canon, will tell) but that's what these forums are for!