after many years of node/js programming, I decided to learn typescript but am facing familiar (to many, as evident by SO questions) roadblocks and wondering if this pain is worth it.

My compiler options are

{
    "compilerOptions": {
      "outDir": "./dist",
      "allowJs": true,
      "target": "es6",
      "esModuleInterop": true,
      "skipLibCheck": true,
      "types": []
    },
    "include": ["src/**/*"],
    "exclude": ["node_modules"]
  }

and yet, tsc checks and carps about wrong types in files in the node_modules folder, and also

src/index.ts:125:21 - error TS2802: Type 'IterableIterator<number>' can only be iterated through when using the '--downlevelIteration' flag or with a '--target' of 'es2015' or higher.

even though my target is set to es6

What am I doing wrong?