IIRC, back in the early days of jet travel, one of distinctions between the British VC10 series and the American B707/DC8s was that the VC10 was claimed to be more pax. friendly, partly because it had humidifiers fitted.
Anecdotal evidence is that in recent times the remaining VC10s -- operated now solely under the banner of Crab Air -- have a well known "issue", particularly in some seats, of condensation dripping on your on head
That suggests they still have the humidifiers fitted, but the higher moisture levels do have a downside.
As to the nosebleeds, I've checked my experiences and although there does seem to be some correlation between nosebleeds and 772 sectors in comparison to other types (774/340), I couldn't claim it to be statistically significant.