Hi,
When you install a new ESP-ADF instance with VisualGDB, it simply clones the Espressif’s ESP-ADF repository and checks out the selected tag/branch. The v2.3 tag of ESP-ADF still references ESP-IDF v3.3.2, so that’s the version that gets installed when you use VisualGDB (or any other tool) to clone it from Github. ESP-IDF 3.x still requires the old toolchain.
If you are confident that ESP-ADF can work with the newer ESP-IDF, you can replace it manually using the git commands and use it with a newer toolchain, however this is something to do at your own risk. We generally try to provide out-of-the-box support for the SDK versions available as official releases, but if you want to try other combinations, please expect to do some research and troubleshooting, as they may need some adjustment.
If you have managed to successfully use VS code to install a different combination of ESP-IDF and ESP-ADF, please share the complete steps you followed to get this setup working (including the screenshots of each step) and we can help you configure VisualGDB to replicate the same results. Please make sure you follow our problem reporting guidelines, as we are not able to provide any help unless we have the specific steps we can analyze/follow on our side.