WordPress tax_query ignoring relation OR

Question

I’ve came up with the not perfect solution to this:

Because I am using term_taxonomy_id I can just add all the IDS and remove the taxonomy specification like this:

  'tax_query' => array(
            array(
                'field' => 'term_taxonomy_id',
                'terms' => array(...all ids...)
            )
     )

And it works! This is a quick solution, although it will work in all of the cases since I can select the desired taxonomies and exclude the non desirable in the process of generation of the query ARGS,

I would still love to know why it was ignoring my OR relation in the first place? Is this a bug or I simply do not understand what OR relation is meant to be?