I can't recommend this "switch". If you are not testing locally with the same relational database as in production, you can miss mistakes and bugs. This is not just theoretical. One example where I thought I will be fine using SQLite was with a small Django project. But time and time again I ran into limitations of either SQLite or Django's database adapter for SQLite, when it came to dealing with many to many relationships in the model and through tables, requiring me to work around the limitations. There is no guarantee, that these workarounds in turn will work the same in PostgreSQL in production.

Anyway, it is a basic practice of keeping test and dev environment as close as feasible to production, to avoid missing issues and wrong assumptions.

That's kind of risky considering the radical differences between types in SQLite and Postgres. There are plenty of situations where EF will need to be configured differently in order to map your .Net types correctly to each DB. Or subtle differences in behavior due to storage differences (particularly SQLite's predilection for storing things as strings). It's so trivially easy to run Postgres in Docker that I don't really see the advantage of using SQLite for local dev.

EF Core is so easy to turn into a disgrace for performance, developer experience, AND build times...