POM version 4.1.0 gets (partly) rewritten back to 4.0.0

[sewe]

A valid POM conforming to version 4.1.0 of the format and starting with

<project root="true" xmlns="http://maven.apache.org/POM/4.1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.1.0 https://maven.apache.org/xsd/maven-4.1.0.xsd">
    <modelVersion>4.1.0</modelVersion>

gets rewritten to

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.1.0</modelVersion>

Essentially

1. the namespace and schema URLs get changed to 4.0.0,
2. attributes not part of the 4.0.0 model (project/@root) get removed,
3. but the project/modelVersion curiously remains unchanged.

I would expect tidy:pom to preserve all of the original, except for possibly reordering attributes.