"Everything" expects you to use MSSQL, even if today there's ok official support for PostgreSQL and SQLite. Most "thought leaders" of various sorts are on Windows and expect you to use it. This pervades throughout the ecosystem.
Can't see this ever changing as it's not in MS' interest to turn other operating systems into good .NET development platforms.
These days I just use EF with Sqlite on 99% of my projects.
SQL Server is the flagship database project on the Microsoft side and that team surely has some imperative to facilitate the EF vision. It simply must be less of a priority for the PostgreSQL and SQLite maintainers to do so. Is that really a valid dig on the .net ecosystem, though?
The community is being diluted by…a different demographic!
Just curious.. what language(s) are you using now?