Firebase Realtime was basically a Mysql instance which Google ended up with when they bought the Firebase ecosystem. Not scaleable at all. You see hints about t

Firebase Realtime was basically a Mysql instance which Google ended up with when they bought the Firebase ecosystem. Not scaleable at all. You see hints about this in some places when they talk about using it in production. I am sure some Google engineer went nuts when he saw what they have to support now. Firestore is a complete engineered Google solution based on the Google Datastore but with added features from recent years (spanner, cloud functions). This is very obvious if you compare the limits between Datastore and Firestore. IMHO they are not really comparable.