Bandwidth has little to do with it.
Most web hosting providers actively manage the load on their servers by ensuring that they are not packed with clients, and moving high load clients to more capable machines.
The company involved (and their resellers and agents, that compose the vast majority of the "other" hosts that have followed suit) decided to target UBB rather than the clients that, very frankly, have no business being on shared hosting in the first place.
In other words, their solution was not the proper one for anyone involved. The small handful of sites running large, overloading UBBs should have been moved to more capable servers, and the clients should have paid the $$$ required to do so.
We invite the ban to be lifted - 6.1.0, with the Accelerator, is lighter on the server than any previous UBB. If they can manage their server and meet the needs of their clients properly, then there should be no problems whatsoever.
