For production setups, you usually want high-availability. So unless you use it on a network file system like EFS (which the SQLite author recommends against), SQLite is not an option.
Not all production setups require >99.999% availability. There are many cases when it’s OK to use a VM with periodic snapshots/backups. In case of a HW failure (which doesn’t happen often) you can recover from a snapshot. An advantage is than an app with a DB in a file (no HA) requires almost no maintenance work.
But it just so happens that I’ve seen in the real world so many single instances of Oracle, PostgreSQL, Maria/MySQL, SQL Server etc. that I know in practice there is a big difference between what someone needs/wants and what someone gets.
A lot of that has also to do with the complexity of setting up HA instances of such databases. Also this is simpler with HA sqlite setups.