That's a pessimistic and imo unwarranted attitude. There are absolutely platforms that maintain backwards compatibility for decades on end. The most salient example is the linux kernel, but—-well, linux distributions are not a monolith. Fine. How about the c language, or common lisp? Perl packages are installed relatively globally, and things don't really break. And sure there's some fragmentation there, like with sbcl-only lisp packages, or gnu extensions, but by and large I can compile an arbitrary perl/common lisp/c package with an arbitrary implementation of that language and, at least in the case of perl and lisp, it works basically the same way it did 10 years ago. This is possible, because it has happened.
I will grant, however, that it is hard. Newer languages—rust, c#, java, python, js—are trying. Of them I would say rust is the best, followed closely by c#, with python and js taking a distant 3rd and 4th, but none of these match the older languages. But—rust is newer than c# and java and python and js. They decided: we're going to make a high-quality, stable package repository, with a culture of stability in packages. And aside from stuff requiring nightly, that seems to be happening, it's still pretty good, and it's still a hell of a lot better than linux. Granted, linux has a much more difficult situation to wrangle, and because it's less monolithic than those other constructions, tragedy of the commons tends to occur, but I think all it takes is a group of people deciding that they will take the work to make things right, getting support, getting lucky, making a super-dynamic linker, and we can fix this.
I will grant, however, that it is hard. Newer languages—rust, c#, java, python, js—are trying. Of them I would say rust is the best, followed closely by c#, with python and js taking a distant 3rd and 4th, but none of these match the older languages. But—rust is newer than c# and java and python and js. They decided: we're going to make a high-quality, stable package repository, with a culture of stability in packages. And aside from stuff requiring nightly, that seems to be happening, it's still pretty good, and it's still a hell of a lot better than linux. Granted, linux has a much more difficult situation to wrangle, and because it's less monolithic than those other constructions, tragedy of the commons tends to occur, but I think all it takes is a group of people deciding that they will take the work to make things right, getting support, getting lucky, making a super-dynamic linker, and we can fix this.