VS Code is trying hard to be an IDE for all languages. If you use pure VS code without extensions, it quite snappy. But as you start adding more and more extensions, it starts slowing down and that too quite fast.
After adding around 10+ plugins on Atom it not only became slower but it started crashing or having internal errors.
With VS code I have 17 plugins installed and it still feels light enough. Personally I disable most plugins until I need them and I think most people should do the same considering how easy it is to disable a plugin.
I have all my language specific plugins disabled until I need to use them.
Does/would a high-end (e.g., Xeon-class) processor and/or a boatload of RAM help keep Code's performance snappy?
FWIW, I run my Code install quite light since my "duties and responsibilities", ahem, only require a few languages/data types, ergo, I am not pushing it hard at all.
FTR, I have a (licensed) install of Sublime, which I confess is snappier than Code, but the difference is so small I use whichever one is better for the task at hand and any difference dissappears under the pressure of an outage enforced deadline :-D