One of my professors said you don’t need an IDE, the Linux system already is a development environment.
Considering “the Linux system” is literally anything you throw on top of the kernel called Linux, it can be a development environment or anything you want it to be. But I think part of the appeal of an IDE is how all the parts integrate (the “I” in “IDE”) so a bunch of packages thrown together might not provide the same cohesive feeling.
“New” Microsoft isn’t really any better, and although Codium itself is perfectly fine (Electron notwithstanding) many of Microsoft’s extensions only work with/are only licensed for the official VSCode build and include proprietary parts.