Do you think they can be powerful enough to build production-grade applications some day or are they going to stay as educational tools or build into specific applications forever?
By visual, you mean node-based?
There are other ways to structure and edit programs than just a bunch of source files that we manually edit through a text editor. For instance image files as in Smalltalk. I don’t see any reason why a visual representation couldn’t succeed in this regard. The issue, imo, is that text is really nice to work with, and it would require a very nice visual editing experience to beat the text based tools we have today.
LabVIEW is largely visual and used to build production grade applications in engineering.
I loved teaching Scratch. And I’ve written about DRAKON - https://shkspr.mobi/blog/2023/04/why-arent-there-more-visual-programming-languages-an-ode-to-drakon/
I think they’re useful for building algorithms. But the tools themselves aren’t powerful enough for anything too complicated. I hope that changes though!