I'm just saying it's a sign, or a smell. Just as you say older/pre-modern -- bad code or not, the same caveat applies about upgrading core language platforms.

I'm just saying it's a sign, or a smell. Just as you say older/pre-modern -- bad code or not, the same caveat applies about upgrading core language platforms. Even a strictly typed language with a much more standardized API like Java can be hard to upgrade major versions (where I would consider 5.3 a new major version).