SQLite is one of the best pieces of software I have used in my career as a developer. It is performant, reliable, simple and consistent. There is a reason sqlite3 is deployed in so many places.
I think it's not used widely enough yet. For example, 99% of websites could benefit from using SQLite instead of MySql or (god forbid) PostgreSQL. I mean Postgres is a fine piece of software but if your website gets 500 visits a day, you don't need Postgres; just use SQLite.
On the flip side, setting up a PostgreSQL instance is so easy now with docker that you could go ahead and use it with a fraction of the admin overhead that it used to require: