But two years is impractical and Debian gets a ton of friction over it. Web browsers and maybe one or two other packages are able to carve out exceptions, because those packages are big enough for the rules to bend and no one can argue with a straight face that Debian is going to somehow muster up the manpower to do backports right.
But for everyone else who has to deal with Debian shipping ancient dependencies or upstream package maintainers who are expected to deal with bug reports from ancient versions is expected to just suck it up, because no one else is big enough and organized enough to say "hey, it's 2026, we have better ways and this has gotten nutty".
Maybe the new influx of LLM discovered security vulnerabilities will start to change the conversation, I'm curious how it'll play out.