Yes, bzip3 compresses that 1GB text file into 170 MB while zstd needs 213 MB (SI units, from my own tests with the "enwik9" file of the GP's page, and the latest releases of both programs, same commands). But the decompression (memory and speed) is a different story.

On my desktop, decompressing with zstd requires 128 MB and 1 s, while bzip3 uses 3.2 GB and 90 s.

Without `-b 511`, bzip3's ratio decreases and decompression requires about the same memory as zstd. But the decompression is still two orders of magnitude slower.