BU has known attack vectors, it's part of the BU "design".
The BU concept is presented as that everyone is perfectly rational and has perfect goodwill towards BU, and so picks a sensible figure that everyone can handle. The reality is the soft 16MB limit can be quickly and easily reached if someone malicious floods the network with 16MB signalling.
its called a sybil attack.
a malicious core loving pool can also sybil attack with loads of core nodes flooding the network and then make changes too..
same thing. nothing specific that is only attackable via BU
Also, BU wasn't (in the past) programmed to follow the longest PoW chain. That would cause the BU blockchain to fork spontaneously into different blockchains
nope
learn consensus and orphans
as long as there's sufficient disagreement between the nodes about what the blocksize should be (a minor incident like this happened recently with a BU mining node, implying these kind of risks are still programmed into the software not as a bug, but as a feature).
and that block was orphaned in 2 seconds
orphans happen daily. orphans are a protection mechanism. orphans are good. yes it causes drama but the end result is a single chain
pools know orphans have a positive job of cleaning up the disagreements. pools also know they cause drama for the community so pools usuallly dont do anything to cause much drama.
hense why pools would take baby steps, testing the water and seeing how much orphan drama is or is not caused.