Can we use `locate_template()` for other than "Template files"?

wordpress-locate-template.php

<?php

/**
 * We need to load this file only if it exists:
 * - first checking in child theme,
 * - then trying parent theme.
 */
$file_path_relative = 'assets/css/for-processing.css';

	/**
	 * If we could use `locate_template()` function for any file
	 * (and not just for "Template files") in WordPress themes,
	 * our job is much easier: a single line of code.
	 *
	 * @link  https://developer.wordpress.org/reference/functions/locate_template/
	 * @link  https://developer.wordpress.org/themes/basics/template-files/
	 */
	locate_template( $file_path_relative, true, false );

// ...OR...

	/**
	 * On the other hand, if `locate_template()` file should be used
	 * for "Template files" only, we are stuck with this code instead:
	 */
	$file_path_absolute = array(
		'in_child_theme'        => trailingslashit( get_stylesheet_directory() ) . $file_path_relative,
		'parent_theme_fallback' => trailingslashit( get_template_directory() ) . $file_path_relative,
	);

	if ( file_exists( $file_path_absolute['in_child_theme'] ) ) {
		require $file_path_absolute['in_child_theme'];
	} elseif ( file_path_absolute_exists( $file_path_absolute['parent_theme_fallback'] ) ) {
		require $file_path_absolute['parent_theme_fallback'];
	}

// ...OR...

	/**
	 * We could actually optimize more:
	 */
	$file_path_absolute = get_theme_file_path( $file_path_relative );

	if ( file_exists( $file_path_absolute ) ) {
		require $file_path_absolute;
	}

Is locate_template() meant for "Template files" only?

I use my custom WordPress theme framework (and starter theme) in all of my themes. Recently I've run into an issue with ThemeForest WordPress guidelines/review.

As the same issue is affecting my theme in WPORG repo, I'm wondering what's the situation there:

WordPress.org themes

In my Reykjavik theme I'm using locate_template() to load CSS file content (to output buffer) for processing with PHP and subsequently passing the processed CSS into wp_add_inline_style() (see the GIST code above for simplification of the actual process related to locate_template() and possible solutions when not using the function). The theme passed the review process without any issue regarding using locate_template().

But is it possible that this usecase is not allowed in WPORG either and the review team just has't spotted the code during the review process?

ThemeForest themes

Due to word "template" in locate_template() function name, ThemeForest WordPress guidelines does not allow using the function to load any other than WordPress theme "Template file".

So, which is correct?
Should I use it for "Template files" only?
Is it even possible to use the function to check for (any, none template) file existence in child/parent theme?
Or should I not use locate_template() function at all in my themes? (I don't think this is the case.)

Additional info

There is no other function in WP that reproduces functionality of locate_template() that I can use to load any file from the theme:

• using theme relative file path,
• checking child theme before falling back to parent theme,
• outputting empty string (nothing) when file is not found,
• plus the function take an array of files as argument too (which I'm not using here).

For reference: Asked for opinion in #themereview WP Slack.

Alternative solution is using a dedicated file loading/locating PHP class in your WordPress theme.