The tool you're referring to is our "Product Version Comparison Tool," which was a web page on our old support website outlining new features and system requirement changes between any two product versions.
A direct equivalent for this tool isn't on this support website; however, all of the previous contents are still available as articles within our Knowledge Base. The System Requirements for each version are stored within the Documentation section, and the new features are listed by product and version in our Release Notes section.
It is on my radar to create the tool again, but I don't an estimate of when I'll start coding it. One of the driving factors for creating the original tool was to avoid downloading and reviewing several PDFs. Since our new Knowledge Base has the same content directly available as public-facing web pages, the current layout also avoids PDFs. Are there other features/benefits I should consider for the new version of the Product Version Comparison Tool?