Agreed. I'm a regular user of the BoM website, and from my perspective the old version was absolutely fine. I wasn't one of the people instantly panning the redesign, but after using it for a while I haven't found positives to outweigh the minor annoyance of the change, let alone justify the expenditure. I can totally believe there were some accessibility issues that I was oblivious to, but it's hard to imagine they couldn't have been fixed in a much narrower, cheaper way.
(It was slightly weird that the old website didn't support https -- but on the other hand, I can't really think of a realistic case where that mattered. And I reckon they could have sorted it out for closer to $0m than $100m.)