You are looking at the HTML representation of the XML format.
HTML is good for debugging, but is unsuitable for application use.
Specify the format parameter to change the output format.
To see the non HTML representation of the XML format, set format=xml.
See the complete documentation, or API help for more information. 
<?xml version="1.0"?>
<api>
  <query>
    <querypage name="Ancientpages">
      <results>
        <page value="20151112183102" timestamp="2015-11-12T18:31:02Z" ns="0" title="Le fil rouge" />
        <page value="20151112234418" timestamp="2015-11-12T23:44:18Z" ns="0" title="Votre ordinateur" />
        <page value="20151112234612" timestamp="2015-11-12T23:46:12Z" ns="0" title="Netix" />
        <page value="20151113002552" timestamp="2015-11-13T00:25:52Z" ns="0" title="Série x86" />
        <page value="20151113125018" timestamp="2015-11-13T12:50:18Z" ns="0" title="Les primauteurs de ce site" />
        <page value="20201030165407" timestamp="2020-10-30T16:54:07Z" ns="0" title="Main Page" />
        <page value="20210814071015" timestamp="2021-08-14T07:10:15Z" ns="0" title="L&#039;IS réseau" />
      </results>
    </querypage>
  </query>
</api>