SiteKit added TagManager unwanted code

Hi, and thanks for great plugin.

Testing site with pagespeed I found out that Google Site Kit add code for tag manager. I allowed adding code for analytics only.
I also tried to create a tagmanager entry to enable “tag manager” section in site kit, edited it to force to not insert code in page.

But this is what I find in html source:

<!-- Snippet Google Analytics aggiunto da Site Kit -->
<script type='text/javascript' src='https://www.googletagmanager.com/gtag/js?id=UA-21xxxxxxx-1' id='google_gtagjs-js' async></script>
<script id="google_gtagjs-js-after" type="text/javascript">
window.dataLayer = window.dataLayer || [];function gtag(){dataLayer.push(arguments);}
gtag('set', 'linker', {"domains":["studiolegaleasmahi.it"]} );

Could you explain me why ?

thanks

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