Some rules in the .htaccess seem outdated.
FilesMatch pattern to protect files and directories form direct access needs to be updated. For instance tpl(\.php)? makes no sense in Drupal 8+.
Configuration for PHP 5 is no longer needed as Drupal does not support PHP 5 since version 8.7.
Overall the current configuration seems too complex and likely can be optimized. The number of rules in the .htaccess may affect server performance a great deal. That's because the file is parsed on each http request including requests for static files.
We may consider moving rules that specific to some directory into a separate .htaccess file located under that directory. For instance there is a large set of rules for serving gzip compressed CSS and JS files.
