Since you are pulling directly from a server's file system, download speeds are often capped only by your own connection.
If you are looking for classic games for research or preservation, there are safer, more curated options than random open directories:
If you’ve ever stumbled upon a sparse, white-and-blue webpage filled with simple text links, you’ve likely found an open directory. For gamers, these directories are often "holy grails" of history, containing ISO files—digital blueprints of optical discs—that allow classic titles to live on through emulation. What is an ISO File?
When users search for "Index Of Games ISO," they are usually using —advanced search strings designed to find open server directories.
The "Index Of Games ISO" is a window into the raw, uncurated side of the internet. It represents a subculture of gamers dedicated to keeping the history of the medium alive. However, it requires a "buyer beware" mentality. For those willing to navigate the risks, it offers a library of digital history that spans decades of innovation.