> Apple shipping minimal security fixes to old OS versions has ripple effects that are really unfortunate and expecting every small app developer to support 5 major versions of the OS feature matrix isn't practical.

I think this is a case where Apple has to make a choice between their developers' convenience or their users' UX. I personally think developers should cater to multiple versions just like any other platform (targeting Android APIs, Windows releases, kernel versions).

Apple developers aren't special snowflakes. They can handle what other developers have been doing for as long as programmable computers existed.