That is interesting! 4k HQ in the R5 is down sampled 8k. If that's by definition. that's a pretty big doozy there! That might confirm both 8k and a 45mp sensor!!!
OR...could this just be a poorly constructed sentence by Canon's marketing people who are unaware of the implications of what high-quality (aka "HQ") 4K means? In other words, does the above sentence imply that there are two 4K quality modes -- HQ 4K and oversampled 4K -- or does it mean that Canon's 4K is simply high quality because it's oversampled?