I added an edited note to the bottom of the blog post.
The original post and the experiments were created before pgvector 0.5.1 was out, and we had not realized there was significant work to optimize index creation time in the latest pgvector release.
We reran pgvector benchmarks with pgvector 0.5.1.
Now pgvector index creation is on par or 10% faster than lantern on a single core. Lantern still allows 30x faster index creation by leveraging additional cores.
https://x.com/pgvector/status/1711910075416432785?s=46
Do you have the code you used so that we can reproduce these results?