A better version

    private async Task ExitEditAsync()
    {
        var state = GridRef?.GetState();
        state.OriginalEditItem = null;
        state.EditItem = null;
        state.InsertedItem = null;

        // This will fix the progressive slowness ---------------------------------------
        foreach (var item in state.GroupDescriptors)
        {
            // Remove the AggregateFunctions since SetStateAsync doubles them
            item.AggregateFunctions.Clear();
        }
        // This will fix the progressive slowness ----------------------------------------

        await GridRef?.SetStateAsync(state);
    }

I used the following code as a temporary fix in our project. The code sets the aggregate function count to 0 prior to SetStateAsync.



    private async Task ExitEditAsync()
    {
        var state = GridRef?.GetState();
        state.OriginalEditItem = null;
        state.EditItem = null;
        state.InsertedItem = null;


        // This will fix the progressive slowness ----------------------------------------
        // List to store GroupDescriptors
        List<GroupDescriptor> grpList = new();
        // Loop through the GroupDescriptors to store them
        foreach (var item in state.GroupDescriptors)
        {
            grpList.Add(item);
        }
        // Clear the GroupDescriptors
        state.GroupDescriptors.Clear();
        // Add the GroupDescriptors back to "state" var
        foreach (var item in grpList)
        {
            // Remove the AggregateFunctions since SetStateAsync increases them
            item.AggregateFunctions.Clear();
            // Add them back without AggregateFunctions
            state.GroupDescriptors.Add(item);
        }
        // This will fix the progressive slowness ----------------------------------------


        await GridRef?.SetStateAsync(state);
    }