Because the roller coaster had a piss poor excuse for adequate restraints on the flagship attraction in the park, limiting the amount of people who are able to ride it. I can also garuntee you that because of the restrictive nature of the design, that it slowed down dispatch intervals significantly. Because of this capacity is reduced, resulting in complaints about long queues (refer to ECG's post as evidence). The extra stuff added to the revamp of the ride is there to give justification to the expenditure, much like X2 was for Magic Mountain. Rather than spending cash on something that isn't going to make the park a dollar in profit, they chose to use the opertunity to reinvent the attraction, in hopes of seeing another honeymoon period out of it.
So regardless of them reinventing anything, from an operational standpoint it was something that was needed. The previous restraint design was virtually a bandaid put on a problem that needed the time and care they're giving it now. It's not always about the aesthetics in projects like this, but more-so improving how the ride runs from an operational perspective. For a roller coaster that lacks a midcourse block, hitting dispatch intervals is extremely important to maintain capacity. Think about that...