I guess I am confused by the parallels you are making?
And I guess Canon's numbering patterns do not help...
But to me the 6 lineage would be: 6D -> 6D II -> RP -> R8...
While the 5 lineage has remained more or less linear (the R is a bit of an outlier), the 6 lineage seems to have split into 8 and new 6 (R6 -> R6 II -> R6 III) that slots between the 8 and the 5.
By the way, I sympathize with your some of your considerations, being myself a non-pro prosumer who likes pro features
Hello! My thinking is this:
At the advent of the R6 / R5 there was no other R camera beyond the R and RP. RP clearly is a 6D2 successor, but I felt that the mantle moved to the R6 when it arrived and the RP simply... remained. So, in my mind, when July 9, 2020 came around the R6 was the natural successor because it had the number 6 and was priced below the R5. It cost more, yes, but so did everything Canon released around that time.
Fast forward to 2025 and I'd agree with your thinking -- or, at least, I wouldn't disagree in many conversation spaces. There's probably an argument that the R8 also exists to placate those who used to buy the x0D series as well. Maybe it does double duty?
Having owned the 80D (well, it was my wife's and now my son's), I felt it was a fun, geeky, and relatively affordable alternative to the much more expensive full frames: it gave the "feel" of an "upscale camera" as seen in the hands of the well-heeled out on holiday, like that stranger who steps onto a float plane in Alaska with their 5Dx amidst the sea of people clutching their Best Buy bodies. Canon kind of lost that feel with the R transition, I think, although cameras like the R8 are probably their attempt to at least slot in a price equivalent. I don't think the R8 spiritually captures what was happening, but it sits at a good price point in the catalog. They'd do well, I feel, to make a mini R5 body in crop form and re-introduce the X0D series as an X0R line -- and that's where the new video functionality they've been pushing for the new gen would fit very, very comfortably for people like my kiddo and his friends. But I agree, it also fills that 6D character as well -- competent, trade-offs, but serves. Someone mentioned earlier here that the R6 is kind of the 5D of yesteryear and the R5 is something new (or maybe the new 5DS/R?), in which case the R8 is now definitely the 6D equivalent.
I'll say this, though, because it's probably not obvious from my limited chatter here: I've had the privilege since 2005 to use a multitude of Canon's digital bodies -- either through ownership or via family and friends. I think they're all great for their time and serve a need or scratch an itch in one way or the other. They all take great photos when used well. I wouldn't turn down the chance to play with any! 600mm of big glass on a Rebel is so much fun, especially if you bring it along with a pal and pretend it's your serious body for the day.
(And the memories it captures today are just as good as when it first hit my bag.)
And yes, the R6 captured a special place in my heart. Like the Rebel and my Mac 512ke, I'll probably never part with it even though I eventually will move forward with the times.
