I have no idea what that page is showing. It's a bunch of figures with no context shoved under three headers.

Is block number the last block number to be processed under the chain? Is it a monotonically increasing number? Is the block hex string meaningful in the context of showing me what's going on (the site seems unable to show me any data related to the non-fork block so who knows.)

What does the difficulty percentage and total difficulty entries mean? How do they relate to each other? The linked reddit post doesn't shed light on it. I am guessing from bits of conversations on that reddit post that "fork" = new client, fork; "non-fork" = new client, no fork; and "legacy" = old client, no fork?

Maybe it's reflecting the difficulty of me figuring out what is going on the page? :)