Yes, this could be an embed on your page using something like https://graphcomment.com/ or an API that you set up on your own server. Source: about 3 years ago

GraphComment works similarly to other comment systems like Disqus. They host the comments for you, and allow users to create an account with a username and avatar on their platform. They provide a free tier for up to 1 million data loads a month. - Source: dev.to / about 3 years ago

I also like WP Rocket's database cleaning tool: https://wp-rocket.me/. Source: about 1 year ago

This will have a serious impact based on that kind of database. A good caching plug-in like WP Rocket should help with the overheads and speed things up. If you have server side caching like memcached or lighspeed make sure you are utilising it. Source: about 1 year ago

Purchase a license from the WP Rocket website (https://wp-rocket.me/). Source: about 1 year ago

Sounds like your colleague bought a nulled/"GPL free" copy of WP Rocket - probably not purchased from https://wp-rocket.me/. Source: over 1 year ago

One of the most beloved WordPress caching plugins is WP Rocket. They’ve managed to take something complex and make it extremely easy, yet still powerful and configurable. They have also made it easy to integrate with a CDN in just a few clicks. - Source: dev.to / over 1 year ago