It took a while, but Garmin did eventually allow for Training Status to be updated by Zwift activities. Connect challenges/badges are still restricted to Garmin/Tacx. Users of other fitness and training platforms have, not unreasonably, asked to be treated similarly and for activities to count towards the challenges. My suggestion is that this could be made a feature of the Connect+ subscription, paying for the required development effort and helping Connect be an alternative data aggregator to Strava.