Why use this over something like sphinx[1], which has quite a rich and established ecosystem? Combine with Furo[2] and it even looks quite similar.
The Furo theme is rather new and borrows some things from Material for MkDocs, for example Admonitions. There's also Material for Sphinx [1], which is a port of Material for MkDocs to Sphinx. Note that it doesn't include all features Material for MkDocs offers.