The formula on the page isn't binary entropy it's this block's contribution to the total Shannon entropy of the supply distribution across the entire chain. Each block contributes −p_i·ln(p_i) to H_total = −Σ p_i·ln(p_i). The "(1-p)" counterpart lives in the other blocks' terms. But the text is ambiguous about this and reads like it's defining a standalone binary quantity. Fair point, will tighten the wording.
It would be amazing to have your eyes on Bitcoin Lens paper
https://bitcoinlens.net/Our website is more a reflection of the paper.