Personal experience, I think. People still complain about python 2.7 even though python 3 has been around for 15 years and python 2 was EOL 3 years ago.
literally to have millions of lines in production code just in our company, untold billions or trillions of production Python2 code that works perfectly fine (well, did work) around the world. guess that will teach us to trust a scripting language for production systems!
So, whats the alternative? Try compiling a decade old java app and get ready for a surprise. Python2 was already dead 2 years ago. If your company did nothing to at least ensure the code runs, thats their problem. All languages go though deprecation and changes, except the dead ones - only if you had used *QBasic, you wouldnt have this problem.
*the choice would be Cobol for most folks, but not only cobol isnt dead, it actually changes and deprecates stuff throughout the years - ex. Cobol77 vs cobol85.
What's the problem? you have the source, nothing is stopping anybody from using python2. In fact from that perspective you could say it is a good thing, once python3 was published, the language python2 became more and more stable. Until we are at this point. The language is super stable. It will never change again. exactly what you wanted.
This is the main difference between trying to get some ancient code written in C working vs "modern" toolchains - if you have the compiler and the code for C, everything is self-contained; many things like python2 download absolutely tons of support code and libraries to "build" - and when those go offline you can't easily build anymore; and you can't even say "this here VM will build this forever" unless you make sure that it will continue to work (and everything is separately cached/downloaded).