Iirc IBM came up with an optimization of the classical algorithm (specifically using enormous but still (barely) practical amounts of RAM) that reduced the adva

Iirc IBM came up with an optimization of the classical algorithm (specifically using enormous but still (barely) practical amounts of RAM) that reduced the advantage of Google's quantum algorithm by an order of magnitude or two. There was two issues with their argument though. First, they hadn't implemented it yet, which is rather ironic considering that Google's feat was in actually delivering an implementation. Second, Google's quantum computer is still orders of magnitude faster than IBM's optimized classical approach, not to mention cheaper.