the chart in section 4.8.12.4 shows that primitive and object types are also valid for style=simple

Author: karenetheridge

versions/3.1.1.md

@@ -1056,7 +1056,7 @@ In order to support common ways of serializing simple parameters, a set of `styl
 matrix |  `primitive`, `array`, `object` |  `path` | Path-style parameters defined by [RFC6570](https://tools.ietf.org/html/rfc6570#section-3.2.7) 
 label | `primitive`, `array`, `object` |  `path` | Label style parameters defined by [RFC6570](https://tools.ietf.org/html/rfc6570#section-3.2.5)
 form |  `primitive`, `array`, `object` |  `query`, `cookie` | Form style parameters defined by [RFC6570](https://tools.ietf.org/html/rfc6570#section-3.2.8). This option replaces `collectionFormat` with a `csv` (when `explode` is false) or `multi` (when `explode` is true) value from OpenAPI 2.0.
-simple | `array` | `path`, `header` | Simple style parameters defined by [RFC6570](https://tools.ietf.org/html/rfc6570#section-3.2.2).  This option replaces `collectionFormat` with a `csv` value from OpenAPI 2.0.
+simple | `primitive`, `array`, `object` | `path`, `header` | Simple style parameters defined by [RFC6570](https://tools.ietf.org/html/rfc6570#section-3.2.2).  This option replaces `collectionFormat` with a `csv` value from OpenAPI 2.0.
 spaceDelimited | `array`, `object` | `query` | Space separated array or object values. This option replaces `collectionFormat` equal to `ssv` from OpenAPI 2.0. 
 pipeDelimited | `array`, `object` | `query` | Pipe separated array or object values. This option replaces `collectionFormat` equal to `pipes` from OpenAPI 2.0.
 deepObject | `object` | `query` | Allows objects with scalar properties to be represented using form parameters. The representation of array or object properties is not defined.