On the standardized charting language, that would be the dream. All agents giving the same spec when they want to build a chart or dashboard, and then having different renderers of that. That is a steep goal. Such a language would need to be simple but still extremely versatile. I'm not sure that combination exists yet. Our language is simple and fairly versatile, but not as versatile as vega-lite itself, or JavaScript code even. Maybe we can evolve in that direction though
I've been mulling extending dbt Charts to support ggplot, and will likely reach out to the team about this in the next few weeks.
The difference is that Vega-Lite, ggsql, ggplot2 are designed to create a single chart. Yes, you can use facet_wrap() to great a series of charts based on a particular variable, but arguably that's still one chart!
What's missing that is table stakes for a BI dashboard: KPIs, text boxes, dropdowns, data sources, governance, and how the charts are arranged on the page and in relation to one another.
In the next few months we hope to ship a JSON schema that represents a dashboard in the same way that a VegaLite does for a single chart.
Does that make sense?