Maybe it just depends on the application. I've been doing frontend development with React and vanilla Javascript for the past 2.5 years, and I can't recall a single user-facing bug caused by improper dynamic typing.
I would push back on the idea that it depends on the application, I think what's more likely happening is that your experience has codified best practices that help to minimize these types of bugs, but you're still manually doing the work to protect against these error with typeof/instanceof and unit tests that validate input parameters.