And yes, even WotC can put something out for 5e and have it not sell if it's poorly targeted. If WotC put out the "Complete Book of Flumphs" as the Winter 2023 hardcover, it's not going to sell anywhere near as well as a Planescape or Dark Sun or a new Magic setting book is.
I just don't see it as remotely controversial to suggest that WotC books sell a lot because they're the official books. The fact that 5e is so widespread makes their books have higher intrinsic value than a comparable 3pp book, regardless of quality, simply because the barriers to use it (and discuss it) are so much lower.
ncG1vNJzZmivp6x7prrWqKmlnF6kv6h706GpnpmUqHyqv4xunGaroJqwqq3LZ21yaGNohnC8wKCcZmlhag%3D%3D