Istio deployment using terraform

Is there any elegant way to use Terraform to deploy Istio in AKS?

There is no neat solution because there is no istio provider. Please have a look at these links:
Install Istio on Azure Kubernetes cluster using Terraform
Setting up on ISTIO on EKS cluster using Terraform or Helm

I’ve not tested any of these yet, but I’m going to check this out on gcp using Istio Operator.

I installed Istio with Terraform Helm provider many times and generally everything is fine. Helm in Terraform has own quirks but it might be the fastest method to provision full setup indeed.