And don't listen to some developers claiming their tools already do that, because they don't, otherwise why there is no option to set our desired rmd160 prefix?
Again, the codes already do this.
I know it will be too hard for you to look at VS code on GitHub, or you would have already done it.
Look at keyhunt Cuda. You actually provide it with a list of rmd160s, in binary format, sorted.
If you are merely talking a rmd160 prefix versus full rmd160, there would be no speed up. The full rmd160 is already generated from the public key.
The most time consuming part of address generation is the first step, the actual math part.