Store Text Content of PDF in elastic search

Elastic Stack Elasticsearch
2

I have research around and Seem like ES is already compressed stored field according to this topic Large string fields - Elastic Stack / Elasticsearch - Discuss the Elastic Stack

There is also a settings to compress it even more
Store compression in Lucene and Elasticsearch | Elastic Blog

curl -XPUT ‘localhost:9200/my_index’ -d ‘{
  “settings”: {
    “index.codec”: “best_compression”
  }
}’

Is this setting suitable for our storage optimization if we store millions of document content?