This is a rote complaint but how often do you really notice it? Even on my ancient spare 2010 MacBook Air, VSC is responsive and it uses less RAM than other apps like Teams or Skype, or simply loading Gmail in Chrome. Yes, vim uses less RAM but it also has like 5% of the functionality.
Is it possible that this is specific to particular plugins or languages? I mostly use Python, JavaScript, Terraform, and Rust but I did notice that Java is, as always, a lot more demanding.