You get everything Vscode does, vscode's LSPs, vscode's element rename/jump to definition (which I realise nvim has but I can't get it to work properly and code does it out of the box), live share sessions, built in split panes and git integration etc etc
It carries over everything as far as I can tell (besides the graphical changes obviously), motions, plugins, shortcuts
I'm sure you can achieve most things Vscode does in neovim but using Vscode/ium and nvim is a massive shortcut