The query you are running would show only the posts assigned to this artist if done correctly. If you’re post object field only allows a single value then that value is not stored as a serialized array. What are the settings of the post object field “artist”? Does it allow multiple values? If it does then your meta query should be correct, if it only allows one value then your query should be
array(
'key' => 'artist',
'value' => get_the_ID(),
'compare' => '=',
),
