additional remarks to my original post of Dec.12/2021: It ist NOT the behaviour of 2-factor-authenification ! It MUST be a problem within kdepim/akonadi-google-resource. Why: I have installed too Manjaro Linux AND Debian Testing (both in virtualbox). Same result -> no syncing nor calendar neither contacts of my google-account. Checked my google-account: "Akonadi Resources for Google Services" has access to Google Calendar & Google Contacts.
Anyone out there in the Debian-family who knows how to solve the problem ? Sincerley Herbert S.
