To quote the self-description of PlatformIO: “PlatformIO is a cross-platform, cross-architecture, multiple framework, professional tool for embedded systems engineers and for software developers who write applications for embedded products.” It can be installed as an extension of Visual Studio Code.
VSC together with PlatformIO provide you with a quite powerful IDE for embedded programming and debugging. It is probably too powerful for beginners, but attractive for people who find the Arduino IDE too limiting.
PlatformIO supports debugging of debugWIRE MCUs in two ways. It offers a simulator, and for the ATmega328, it provides the remote stub solution described on the Embedded Debugging page. However, it is pretty easy to integrate other debugging solutions. You must specify in the platformio.ini project file how to interact with the debugger. The readme file of dw-gdbserver provides an example for that.