[Sage 9] Taxonomy template isn't used (but in search path)

Although the Debug plugins list the resources/views/taxonomy-flavours.blade.php as one template file for loading, the file isn’t actually used, the default templates are used, I even tried to cause any effect by just using @php echo 'Test!'; exit; @endphp in the template file taxonomy-flavours.blade.php, but nothing changes.

What could interfere with the actual usage of the taxonomy template file, although being in the WordPress lookup list?

Related to this resolved issue: [Sage 9] Taxonomy template - #2 by alwaysblank