It estimates 79.6 bits of entropy. It's basing the estimate on just the words, not on the popularity of the phrase as a whole. Let's compare that to https://ww

It estimates 79.6 bits of entropy. It's basing the estimate on just the words, not on the popularity of the phrase as a whole. Let's compare that to https://www.grc.com/haystack.htm https://www.grc.com/haystack.htm which many people promote as a good password checker, but is actually terrible. It claims 177 bits of entropy. This is basing the estimate on just the individual characters.