Considering that the vines only drop a certain percentage of the time when mined without a tool I'm pretty sure this is the intended behaviour.
Added some additional pictures with a modified default texture to better illustrate the issue.
Also occurs during the "victory dance" animation.
Did some testing with single biome worlds, and yep, this is just a coincidence. I'll make a feature request instead. Sorry!
I'm not saying the spawning of the Brutes themselves is biome-dependent, I'm saying it might be affected by a similar issue to nether fortresses since the mob cap in the soul sand valleys is less likely to be filled. I've tested multiple bastions in these two biomes and the incidence of Piglin Brutes is much higher in the Soul Sand Valley. Please reopen the issue.
Also, if the Piglin Brute spawning is random among the Piglins, why do they spawn in the same number and positions when I generate the world again with the same seed?
This might actually be a resource pack issue. After disabling my resource pack (one which only changes textures, I should mention) I was immediately able to get a C418 track to play through /playsound. Either that, or I've just been very unlucky before this. I'd have to test a little more.
Apparently I was just getting very unlucky when testing this issue. For whatever reason in 20 attempts I hadn't encountered anything other than the new tracks when using the command, but now after a few attempts I'm able to get the old tracks to play.
There is no confirmation that the issue I've mentioned is intentional behaviour in the first place. Please re-open the issue.
Unable to reproduce in 1.17_rc2. Bees work perfectly fine.
Honey level increases when bees exit the hive, not when they enter. Bees will also remain in the hive if it's broken in creative mode or with a silk touch tool in survival.