https://stackoverflow.com/q/61917718/1271826

ViewController.swift

class DriverAnnotation: NSObject, MKAnnotation {
    var coordinate: CLLocationCoordinate2D                  // if this can change, I'd suggest making it `dynamic var`; if it can't change, I'd make it constant with `let`
    var uid: String

    init(uid: String, coordinate: CLLocationCoordinate2D) {
        self.uid = uid
        self.coordinate = coordinate
    }
}

class ViewController: UIViewController {

    @IBOutlet weak var mapView: MKMapView!

    lazy var locationManager = CLLocationManager()

    override func viewDidLoad() {
        super.viewDidLoad()

        if CLLocationManager.authorizationStatus() == .notDetermined {
            locationManager.requestWhenInUseAuthorization()
        }

        // works if you add this
        //
        // mapView.register(MKPinAnnotationView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultAnnotationViewReuseIdentifier)

        // works if you add this
        //
        // mapView.register(MKMarkerAnnotationView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultAnnotationViewReuseIdentifier)

        // works fine if you do neither of those, too
        
        let center = CLLocationCoordinate2DMake(37.332, -122.03071)

        mapView.camera = MKMapCamera(lookingAtCenter: center, fromDistance: 1_000, pitch: 0, heading: 0)

        let coordinate = CLLocationCoordinate2DMake(37.332693, -122.03071)
        let annotation = DriverAnnotation(uid: UUID().uuidString, coordinate: coordinate)
        mapView.addAnnotation(annotation)

        mapView.userTrackingMode = .follow
    }
}

FWIW, this is what results:

FWIW, it does appear that the displayPriority of the annotation view is defaulting to .defaultLow (although the documentation suggests it should default to .required.

So you might want to declare an annotation view class, that sets it to .required:

class CustomAnnotationView: MKMarkerAnnotationView {
    override init(annotation: MKAnnotation?, reuseIdentifier: String?) {
        super.init(annotation: annotation, reuseIdentifier: reuseIdentifier)
        displayPriority = .required
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override var annotation: MKAnnotation? {
        didSet {
            displayPriority = .required
        }
    }
}

And

mapView.register(CustomAnnotationView.self, forAnnotationViewWithReuseIdentifier: MKMapViewDefaultAnnotationViewReuseIdentifier)