It's only when you subjectively remove all the features that you don't care about that it becomes doable to make smaller editors. And that's fine. But you can't have your cake and eat it.
The reason most people don't care is because it simply doesn't matter. Not even a little bit. Laptops are cheap. Memory is cheap. CPU is cheap. Your time is not. And it takes investing your time to make this stuff more optimal and faster. And VS code just does a lot of nice things that make you more productive. I use Intellij myself which uses even more resources. But it's a bit smarter and saves me even more time. The point with both is that you lose more than you gain by replacing them with something faster. It's not worth it.
My first computer was a commodore 64, so I'm well aware what that thing could do (and couldn't do). I'm writing this on a M1 macbook. Orders of magnitudes faster, doing things I could not imagine back when I had a commodore 64, etc. You can have one second hand / refurbished for next to nothing. Basically below my day rate when I'm consulting.