Why use ConfigureAwait(false) in async database layer operations? [duplicate]

I am trying to get my head around ConfigureAwait(false) and came across this https://devblogs.microsoft.com/dotnet/configureawait-faq/ From what I understand, and please correct me if I am wrong, is that ConfigureAwait(false) should be used when we are NOT sure of the calling SynchronizationContext's queuing capacity for tasks, or a potential for a deadlock.

We have asp dotnetcore project where we expose few endpoints for CRUD operations on certain functionality. In the database layer of this project, I came across code like:

public async Task<SomeType> CreateItemAsync(Item item, DateTime startDate, DateTime endDate)
{
    await using var connection = SqlConnection.GetConnectionAsync();
    try
    {
        var item = await connecion.QueryAsync<int>(....).ConfigureAwait(false);
        if(item == null)
        {
            throw new DatabaseException($"failed to insert item");
        }

        var subItemsTasks = new List<Task<int>>();
        subItemsTasks.Add(connection.QueryAsync(...)); //subItem1
        subItemsTasks.Add(connection.QueryAsync(...)); //subItem2
        subItemsTasks.Add(connection.QueryAsync(...)); //subItem3
        ...
        ...

        await Task.WhenAll(subItemsTasks).ConfigureAwait(false);
        return await connection.QueryAsync<int>(...).ConfigureAwait(false);
    }
    catch (Exception e)
    {
        throw new DatabaseException(...);
    }
}

Is this a good pattern to implement? Also, do we need ConfigureAwait(false) on Task.WhenAll() when it is already called on a different synchronization context than original. Same for the return statement configure await.