Updated VS2019 and now my output is full of Info-level junk.

The following is my standard blurb for intellisense problems, but I suspect some of the updating will fix your excessive-warnings issues:

This may help you with intellisense problems:

Also, try update the VSCode package inside of Unity: Window → Package Manager → Search for Visual Studio Code Editor → Press the Update button

Also, this: No suggestions in Vscode