In some way, by indirectly helping fix this bug, they led to a ~10% performance increase for everyone who was using that faulty compiler! That's even better than an optional flag that many people won't know about or use.
That performance regression only hit code that was using a very large number of paths with the same table of computed gotos at the end. That's likely to only be relatively complex interpreters that were affected. So it's not a broad performance improvement. But it is nice to have an example of the compiler's new heuristic failing to prove evidence it needs to be tunable.