>What non-ideological motivation do I have to ration computing resources on my IDE?

I feel gross explaining this.

If we both have the same exact machine, but I choose to use software that uses substantially less resources -- well -- then I get to run more of that software simultaneously.

if you use computers as some big single-tasked typewriter equivalent then yeah, who cares.

it's not all fucking style and ideology, sometimes behaviors have a decent concrete reasoning.

I don’t see a lot of Photoshop or Premiere Pro users giving up the complexity and functionality of their programs just to save on memory allocation. They aren’t saying “I’d rather use iMovie for iPad and MSPaint because it uses less RAM.”

Heavier IDEs like VSCode are making a very well-defined tradeoff between resource efficiency and functionality.

The fact that it is web-based makes extensions and design iterations more easy, and it allows it to run on more platforms including web browsers. In my opinion that is a very obviously intentional design decision.