Below is a one liner example how to remove both <ins ... ></ins> and <script> ... </script> tags:
✗ ls *.html | xargs sed -i.bak -E '/<ins\b[^>]*>.*?<\/ins>/d; /<script\b[^>]*>.*?<\/script>/d'
✗ rg -in adsbygoogle * | more
✗ find . -type f -iname \*.html.bak -delete
✗
Perlapproach is well-suited for multi-line processing: