We are arguing that support for older versions of software is important, be it operating systems or client software. Support here means "keeping things running as they are", translating primarily to security patches with no frills attached.
Everyone is happy that Debian Unstable offers brand-new software in a rolling release, but their up-to-date LTS offering is also highly sought after.
I understand, thanks. I pointed out in another comment that Mojave support ends in 2021 which will have been 10 years since Adobe CS6's release. The grandparent seems to be arguing that they are entitled to support beyond that.
I get that Windows (for example) backward compatibility is even longer. That's great but involves trade-offs I don't think operating systems should be expected to make.
Everyone is happy that Debian Unstable offers brand-new software in a rolling release, but their up-to-date LTS offering is also highly sought after.