Alternative for is_taxonomy() to workaround theme's default sidebar

Question

My Wordpress theme is using some code in the "sidebar.php" file that tells it that some pages should always use the default sidebar. This was fine until I found that each and every custom taxonomy (example: "taxonomy-mountains.php") page is defaulting to this default sidebar.

I thought about catching this with is_taxonomy(), but that's deprecated and won't work. Any better programmers out there with an idea of how I could fix this now. Something like if(is_taxonomy('mountains')){} would've worked fine. Below code is an excerpt, if you think something is missing let me know.

//Default sidebar
$selected_sidebar_replacement = 'Sidebar Widgets';

//If is page or single
if(is_singular()){
global $wp_query;
$post = $wp_query->get_queried_object();
$selected_sidebar_replacement = get_post_meta($post->ID, 'sbg_selected_sidebar_replacement', true);

//If default selected
if($selected_sidebar_replacement == '0' || $selected_sidebar_replacement == ''){
$selected_sidebar_replacement = 'Sidebar Widgets';
                    }

// Reset the global $the_post
wp_reset_query();

                }

Answer 1

The function that replaces is_taxonomy() is named taxonomy_exists(). Than there's also is_tax() and is_tag() that check if the query is for a taxonomy archive page.

EDIT

$selected_sidebar_replacement == '0' || $selected_sidebar_replacement == '' won't work. You're not checking the type.

Better do it like this:

if ( ! $selected_sidebar_replacement OR emtpy( $selected_sidebar_replacement ) )