The helm chart contained in "istio-0.8.0-linux.tar.gz" (generated from make istio-archive VERSION=0.8.0 ISTIO_DOCKER_HUB=gcr.io/istio-release) is still version 0.5.0.

It's worth noting that, according to Chart.yaml's documentation,
"version" is the chart's version, while "appVersion" is the inner application's version. That is, the chart's version need not be 1-to-1 with Istio.

/cc @mandarjog