Is it possible to use eks role assumption for service accounts with the gitlab helm chart?

We run our gitlab instance on K8s. Instead of using keys to access storage we would like to use this native feature
to access gitlab storage (s3 buckets etc).
this documentation

suggests that you need kube2iam or kiam to do this. My question is does gitlab actually support using native role assumption now via the official helm chart or are there features missing to allow this to work? Our testing indicates this does Not work as we get 403 denied on all buckets while trying to annotate service accounts with the correct arn.