i've had strings of bad runs like that before, but i've also had strings of very good runs with lots of feathers/feathered crests, minor vigor, attunements/survivors, and golds. It's just luck, pure and simple. I was kegging and had the same experience with bad runs in a row, then a guildie advised me to zone out go do a mission and that will "reset" the anti-farm code..after a 10 min debate in guild chat about it, I did a quick mission - came back to kegging and guess what?...a no gold/tome/glacial stone run! The very next run, 5 golds, 2 tomes and some stones...long story short, it doesn't matter imo...just keep farming them and your good runs will come. Just to be sure though, I'll try a Jaya Bluff (solo NM r/rt) run right now and report back
EDIT: 6 feathers, 9 feathered crests, a radiant and a vitae...126 gold...i haven't merched it yet, so dunno what total value of all drops are, but needless to say the feather count was a much lower than average, but 10 more runs like this and I would feel comfortable in saying that something has changed. I'll do a few more and report back again.
AND
1 more run...this time more feathers and more crests, 2 gold and an attunement rune....overall a better run and this is the 2nd of two in a row...so with an upward trend, albeit an insignificant sample size, it's hard to convince me that it has been nerfed....