Do you have a "why Vizro" kind of explanation somewhere? Would be really helpful early in the docs, or on the GH readme.
Regarding "why Vizro": As we all know it is hard to compare tools like for like, but we see Vizro as a great combination of benefits offered by existing tools (given that some have been mentioned on this thread); it leverages a simplicity and low-code solution approach, but it still enables users the flexibility to customize advanced solutions. It keeps configurations simple even if you create more sophisticated actions/callbacks. It comes with an out-of-the box sophisticated look and feel.
The approach of using a configuration layer to enforce standardisation in the way that components and code is assembled utilises a grammar which is largely tech agnostic, and while it is currently optimised to leverage Plotly and Dash, it could theoretically utilise components from other packages such as StreamLit in future