At a previous job, the frontend was a ClojureScript codebase dating back to around 2013, with a React-based UI. The codebase survived a decade of major upgrades to ClojureScript and React, and many chunks of code in git blame dated back to 2013 - 2014. For reference, ClojureScript's first public release was in 2011, and the React wrapper the codebase used dates back to December 2013.
I think the strong focus on backwards compatibility is what helped ClojureScript (and CLJS libraries we used) stay largely unchanged, but we had plenty of "React code" that wasn't changed at all between 2013 and 2022 since it met business requirements and "just worked".
Unfortunately, I don't work there anymore, but I don't see why it'd be impossible to build the early version of that frontend today. Recently, I've been using TypeScript for frontend, and the codebase is still surviving major upgrades to React, TypeScript, and the various libraries we use.
However, I will admit that the pace at which libraries release is extremely fast compared to other ecosystems I'm familiar with (Clojure, Java, Rust, etc.).
I think the strong focus on backwards compatibility is what helped ClojureScript (and CLJS libraries we used) stay largely unchanged, but we had plenty of "React code" that wasn't changed at all between 2013 and 2022 since it met business requirements and "just worked".
Unfortunately, I don't work there anymore, but I don't see why it'd be impossible to build the early version of that frontend today. Recently, I've been using TypeScript for frontend, and the codebase is still surviving major upgrades to React, TypeScript, and the various libraries we use.
However, I will admit that the pace at which libraries release is extremely fast compared to other ecosystems I'm familiar with (Clojure, Java, Rust, etc.).