The other thing we've encountered is that vectors take up a lot of storage space compared to the normal columns (easily a couple kb per row). You can fill up a db really quickly, especially if you're embedding really small chunks
Because ideally they hold massive, well optimised indexes in their memory to be able to search quickly and not miss any vectors.
We have seen similar products in the olap space, as well, ie. Clickhouse local.
So many existing DBs can already do vector search, do we really need one dedicated to just that?