These are Google Apps which are not installed with /e/. First paragraph of the article explains this.
Google’s Messages and Dialer apps for Android devices have been collecting and sending data to Google without specific notice and consent, and without offering the opportunity to opt-out, potentially in violation of Europe’s data protection law.
Tl;dr: Dialer is not trying to connect to Google, it was microg
Although the /e team changed some? aspect of the dialer app, Google seems stil sitting anywhere inside and is serving some purpose for Google (or the user who wants / need this ;- )
I installed a Samsung S5+ e-0.22-p-20220213163416-dev-kccat6 and setup the included SIP VoIp client (SIPAUA/0.1.001) and probably this app tries to connect mtalk.google.com
Addendum: Perhaps not connected to this app but initiated from MicroG, there ist a configuration option to disable device registration / google cloud messaging. Some effects associated with it
Add2: Also with disabled Google device registration & disabled Google Cloud mesaging the phone still want to contact mtalk .google .com. Interestingly: Google SafetyNet ++cannot++ be disabled! possible, but microg uses its on logic ;- )