Firestore automatically indexes all fields in all collections adding to storage size and slowing write performance.

We can add single-field exemptions but we need to list all fields separately and there is a database-wide limit of 200 field exemptions.

In a highly optimised use case we would want to index only specific fields that we know we query on, and just exclude all others.

It's almost like the current behaviour is a database for novices, but we can't optimise for serious production.

We need either a wildcard exclusion, or effectively just a switch/setting that says "only fields with explicit index definitions".