‘template_url‘ / ‘template_directory‘ – URL of the active theme’s directory. Within child themes, both get_bloginfo(‘template_url’) and get_template() will return the parent theme directory. Consider echoing get_template_directory_uri() instead (for the parent template directory) or get_stylesheet_directory_uri() (for the child template directory).
Source: https://developer.wordpress.org/reference/functions/bloginfo/
the function get_template_directory_uri() is the better one, if you want to support creating child themes. if you don’t care, it shouldn’t matter much.
edit:
did a simple speed test and found no significant difference:
blog_info('template_url') 0.00010 sec
get_template_directory_uri() 0.00007-0.00010 sec