Repro

{
  "rules": {
    "@typescript-eslint/ban-types": ["error"]
  }
}

function isFunction(value: any): value is Function {
  return typeof value === 'function';
}

Expected Result

The tslint:recommended ruleset for ban-types includes Function
https://github.com/palantir/tslint/blob/master/src/configs/recommended.ts#L23

So I would expect it to be the same in @typescript-eslint/recommended.
I was unable to find any issues about it being intentionally removed.

Actual Result

Function type usage is not banned

Additional Info

To match TSLint I have to do this

"@typescript-eslint/ban-types": [
  "error",
  {
    "types": { 
      "Function": { 
        "message": "Prefer a specific function type, like `() => void`." 
      } 
    }
  }
]

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