proxy_init is not run for envoy on gateway. Most likely because of this, something is missing in the setup such that core dumps don't appear.

• ulimit -c shows unlimited as it should
• core_patterns looks correct (/etc/istio etc)
  I was not able to cause core dumps by sending SIGABRT to any process.
  Also tried setting core_pattern to some other dir (/tmp) which required container to run in --privileged but that did not solve the problem. It's not likely to be a perms issue because envoy anyway runs as root.