SQLite has so many advantages over PostgreSQL.
No deamon. Single file per DB. Less configuration overhead.
Postgres also has many advantages over SQLite.
Supporting more than 1 writer per process. Strict typing. Access controls. Replication at scale is more effecient than copy-pasting files (seems SQLite has improved on this one).
It's probably perfect for a majority of work (and DuckDB takes that even further).
But for big, multi-writer work PG is the way to go.
Postgres also has many advantages over SQLite.
Supporting more than 1 writer per process. Strict typing. Access controls. Replication at scale is more effecient than copy-pasting files (seems SQLite has improved on this one).