Apple is to blame, honestly. Android at least releases support libraries to allow older devices to receive more patches as well as some newer platform features. This is unheard of on Apple's platforms. If Apple changes any code, then they simply push out a new version - if a framework has bugs since iOS 12 and they've fixed it, the fix will only rollout for iOS 16+ users and leave everyone else behind. Security updates are the one exception, but Apple is capable of much more. The company continues to step away from being a steward of good technology.