I wonder how this compares to VarianceCharts - https://variancecharts.com/ (besides the license). They both claim to get inspiration from the grammar of graphics.
As far as I understand from quick review the projects are quite similar. But variancecharts don't have facets and not free for commercial use. Difference in API doesn't matter. Taucharts can be wrapped to webcomponent and described on the page using tag as well.
