They don’t need to do anything. The flag is removed, IIRC, so perhaps config changes. All the writes should be faster by default, because we changed how transactions are run altogether.
There’s a flag which you can use to change the number. We set it by default to 1000. But, you could modify it as you need to. I strongly believe that any single key which has that many UIDs should NOT be served.
If one type has billions of nodes, then instead of using type(X), would be better to retrieve a field which only belongs to that type of node. Then check the existence of that to determine if the type is legit or not.