I'm going to be the hippie and say maybe it's best if instead of one package, we had a family of packages? I think the htmlwidgets do that, with crosstalk binding them together, it's as if it were one package.... Except that there is more functionality than could ever fit (or should fit) into any one package. Consistent with the philosophy of smaller more functional packages.
The counter to this point is that ggplot2 does almost everything... But interactivity includes things like tables, or 1 number infoboxes... Things outside of ggplot2's purview. So maybe many packages designed to work together is the perfect answer? In R we have the tidyverse... For interactive via we have htmltools?
Granted... My answer doesn't say how to make this line chart interactive...