Why restarting Bluetooth is not possible after memory release ?

[dharmikP17]

I was actually facing issue while trying to restart the Bluetooth module in ESP32. I have to do this because I want to use Wi-Fi as well.
When I went into library there were few mentions that restart will not work after memory release.

if (is_start_disabled){
    ESP_LOGE(BT_AV_TAG, "re-start not supported after end(true)");
    return;
}

In end process the function for releasing memory is

if (release_memory) {

        ESP_LOGI(BT_AV_TAG,"disable bluetooth");
        if (esp_bluedroid_disable() != ESP_OK){
            ESP_LOGE(BT_AV_TAG,"Failed to disable bluetooth");
        }
        log_free_heap();

    
        ESP_LOGI(BT_AV_TAG,"deinit bluetooth");
        if (esp_bluedroid_deinit() != ESP_OK){
            ESP_LOGE(BT_AV_TAG,"Failed to deinit bluetooth");
        }
        log_free_heap();


        ESP_LOGI(BT_AV_TAG,"esp_bt_controller_disable");
        if (esp_bt_controller_disable()!=ESP_OK){
            ESP_LOGE(BT_AV_TAG,"esp_bt_controller_disable failed");
        }
        log_free_heap();

        // waiting for status change
        while(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED)
            delay(50);

        if(esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_INITED){
            ESP_LOGI(BT_AV_TAG,"esp_bt_controller_deinit");
            if (esp_bt_controller_deinit()!= ESP_OK){
                ESP_LOGE(BT_AV_TAG,"esp_bt_controller_deinit failed");
            }
            log_free_heap();
        }
    
        // after a release memory - a restart will not be possible
        ESP_LOGI(BT_AV_TAG,"esp_bt_controller_mem_release");
        if (esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT)!= ESP_OK){
            ESP_LOGE(BT_AV_TAG,"esp_bt_controller_mem_release failed");
        }
        log_free_heap();
        is_start_disabled = true;

    } 

Here also I see comment that restart will not be possible. This is the A2DP library and I have witnessed same thing with BLE too.
Why is that ? And if I want to start Bluetooth again, restarting ESP is the only option ? if yes why ?

Second thing is there are several deinit methods in above function. What if I took them outside and leave only memory release function in there(after release memory comment part). Will Wi-Fi work then without releasing memory ?

However, in Bluetooth Serial this is not the case, I can end and begin process again without any issue. Again but in Bluetooth Serial end method runs all deinit methods shown above except memory release. So I think it does not need particular mechanics that are necessary for a2dp and BLE, Am I right ?