I think this is only a problem when working unplugged. I have visual studio code sitting idle all the time and it really doesn't seem to slow down my system. It generally only uses about 500MB of RAM with two windows open with multiple tabs on each. I have 16GB of RAM but thats not much compared to today's standards.

Sublime text using 300mb of RAM is a little odd. Generally in my case, its uses around 20-25MB with 50+ tabs opened.