Rampage455

Might not be a bug. Some mobs can still spawn with doMobSpawning set to false. For example, the ender dragon, withers, silverfish from infested blocks, player-made iron golems. Creaking spawns are triggered by the player like the above examples, so it might be intentional that doMobSpawning doesn't affect creaking spawning.

This is speculative, but it may be that they intentionally did not update the behavior of the minecart with furnace to work in the new Minecart Improvements experiment. Jens Bergensten tweeted several years ago (2016) that they would probably try to phase out the minecart with furnace, which is probably why it was never added to Bedrock Edition. It's possible they intend to finally remove the minecart with furnace, and won't bother making it try to function properly with the new minecart behavior.

Not a bug. In the code, the conduit initially chooses a random monster entity within 8 blocks of the conduit to damage, and does not change targets until the original target is out of range or dies.

Is this actually a bug? A code analysis reveals that the only conditions on a block allowing spawning is that it has a solid top surface, and a luminance less than 14. Are we assuming that they are supposed to act like other saplings because they're part of the #minecraft:saplings block group? The block group doesn't appear to affect block properties. Azaleas have a solid top surface, they don't have a luminance, and they don't have an explicit override like some other blocks that restricts spawning. This may be intentional game design.