There are many projects for those who look after them (especially these which are implementing CUDA) that are >100-1000x faster than brainflayer and are available for many years. Some public (some are already gone), some private.
E.g. CudaBrainSecp, you can still find some forks, you can hit 20-80M/s per GPU in dict mode.
Or BrainWords (https://web.archive.org/web/20240130042544/https://github.com/phrutis/BrainWords) (already gone) with 360MKeys/s on RTX 4090 (according to README).
There are some PRs implementing secp256k1 in Hashcat.
So it's not about the speed, but finding the right data and unique ideas. E.g. you can scan the largest dumps from weakpass site in no time.
So if there any combinations of phrases that are available somewhere online, it's already long gone.
At this point I think people does this just for fun or research.

There are already around 20-30k cracked brainwallets which can be found online.
E.g. Privatekeys.pw site publishes (paywalled) some of the weak once. Some sites publishes similar lists as well.