Hello @jrgleason,
Ingress objects are kubernetes native objects, and their contents are defined by the kubernetes project.
IngressRoutes are custom resources that are defined by the Traefik team, and expose more complex functionality that Traefik can provide.
If you are happy with your ingress objects, you can continue to use them, and use annotations and secrets to manage the certificates: (Kubernetes Ingress - Traefik). Many third party projects only work with ingress objects, so this may be your best option.
If you are looking to perform more complex routing, or to take advantage of more features, then you will need to use the IngressRoute objects.