Interactivity is important if interactivity is important, and should be given the attention it deserves, but JavaScript people have always wanted to believe it's always more important than the fundamentals of text-based information, which I'd argue it rarely surpasses in importance.
People like to conveniently forget that even if you're building a richly interactive thing that's better described as an application, all your buttons, labels, chart legends, street names, links, table data cells, blog posts, confirmation boxes, error messages, form fields, comment threads, settings screens, profile names, notifications, product specs, and many more components are going to be text, and should be treated as the venerable vehicle for information that text is. Sometimes it isn't as important as other aspects, but a great foundation in typography will allow for someone to produce great results with less resources.
Typography is still important, but I'm saying interactivity is even more important yet still is a blindspot for most designers. You can imagine two websites, one with subpar typography but excellent responsiveness and interactivity, and the other with excellent typography but is slow and interactions are confusing or don't work perfectly. It's not hard to see interactivity wins.
Many UIs are notorious for bad typography but are still successful because they are responsive and smooth. I like typography but it's useless if the site loads slowly or the navigation is not intuitive, etc.
I suppose you (or perhaps designers) are thinking of interactivity in the opposite order as I am, as though it's a sensible or a necessary step to position some possibly janky animation in-between the visitor/user and what they're trying to accomplish, and it's sufficiently high-risk as to actually cause problems. I initially couldn't think of how some piece of UI would actually ship even though it posed a risk to the user's experience, but now that I do think about it, it's always been a top-down decision, less that of an actual designer; usually it's a bunch of pointless dropdowns or sliders that just weren't given any thought, and engineers or designers were told to do it because 2 weeks gotta go fast gotta ship. There can be some really bad offenders out there, I've worked on fixing them, I just usually attribute that to pointless pressure to build specific things, where implementation details are removed from the agency of their rightful craftspeople.
People like to conveniently forget that even if you're building a richly interactive thing that's better described as an application, all your buttons, labels, chart legends, street names, links, table data cells, blog posts, confirmation boxes, error messages, form fields, comment threads, settings screens, profile names, notifications, product specs, and many more components are going to be text, and should be treated as the venerable vehicle for information that text is. Sometimes it isn't as important as other aspects, but a great foundation in typography will allow for someone to produce great results with less resources.