Hopefully, these labs provided you some idea of why a service mesh is critical when developing and operating microservice applications. Istio is an emerging technology so keep checking the upstream announcements and blog for exciting news.
This workshop wasn't intended to be full training but rather a "taste of service mesh". For a full training experience we recommend you take an official Red Hat course. It'll get much deeper into the concepts and get your ready to run service mesh in your own environment.
Reach out to your Red Hat account rep for getting access to official training.