The regular Visual Studio uses about the same amount of memory as VSCode while being an order of magnitude more complex and feature-rich.
We have a solution with around 30 projects in it - this solution consumes around 1.25gb of RAM in Visual Studio. In contrast, the same solution in VS Code open along with two other windows open to other solutions are using a total less than around 300mb.
Its the main reason I'm excited about Rider.