I'd be happy to help you with this issue!
Firstly, it's great that you were able to achieve an average of 24FPS on the LVGL music demo. That's a significant improvement and a good indication that your M5Stack Core2 hardware is capable of handling the display requirements.
Regarding the TFT_eSPI library, it's true that the built-in library in the M5Core2 library is outdated and doesn't support DMA. However, the newer versions of the library do support DMA and can provide significant performance improvements.
To use the newer TFT_eSPI library with your M5Stack Core2, you need to follow the installation and configuration instructions provided by the library's developer. Here's a general outline of the steps you need to take:
Download the latest version of the TFT_eSPI library from the library's GitHub repository: https://github.com/Bodmer/TFT_eSPI
Install the library in your Arduino IDE using the "Library Manager" option in the "Sketch" menu.
Open the "User_Setup.h" file in the TFT_eSPI library's "User_Setups" directory and modify the settings to match your M5Stack Core2 hardware. Specifically, you need to configure the display type, pins used for communication, and other settings as required by your hardware. Refer to the documentation and examples provided by the library to make these changes correctly.
Once you have configured the library, you can use the library's APIs to draw graphics and text on the display. Be sure to use the DMA-enabled APIs for maximum performance.
If you encounter any issues during this process, feel free to ask for further help. Good luck!