You should of course verify these results in your scenario. However, I somewhat doubt that the person exists who cares greatly about performance, and is still willing to consider bzip2. There isn't a point anywhere in the design space where bzip2 beats zstd. You can get smaller outputs from zstd in 1/20th the time for many common inputs, or you can spend the same amount of time and get a significantly smaller output, and zstd decompression is again 20-50x faster depending. So the speed of your bzip2 implementation hardly seems worth arguing over.
Sure there is: someone provided you bzip2 files. Or required you give them files in that format.
Then you don’t have a choice.
And if you have to use it, 14% is a really nice speed up.