For future reference, DatabinRemove[] still works as of Version 13.2, but it is officially deprecated as it defeats the purpose of Databins. If you're looking for a recordset that you can update/delete items from you're better off using a database like SQL Server, MySQL, Mongodb, Couchdb, &c., as Data Drop is really intended for data capture (there's a difference).

https://reference.wolfram.com/language/ref/DatabinRemove.html

If you need to update a record, you have to delete and then replace.

Yes, DatabinRemove was itself removed (Actually it still works, we just don't guarantee that it will in the future).

The original model for the datastructure was append-only and they decided that it was a mistake to deviate from it. The reason for it being append-only is going to be a long, complicated conversation about distributed algorithms and datastructures, but I'm sure being append only has some important performance characteristic.

There isn't a function for this.

Databins seem like an "append-to only" datastructure for representing a series of values. You wouldn't use databins, for example, to represent an arbitrary spreadsheet. For that I would I CloudDeploy a table of values to the cloud.

You could implement a function to delete a record from a databin, but it would require basically copying a databin and creating a new one.