Metabase not using parallel query when connecting to viable postgres

As on topic,

we are connected to postgress which got enabled in configuration parallel query, but despite of that i see that questions from metabase are using always single core,
i tried to pass to jdbc "set max_parallel_workers_per_gather = 8" but it's ignored or im doing it wrong.

Same equivalent query from pgadmin from same user is using all defined cores

preferQueryMode=simple handled that issue, but not sure is it right aproach