Apple is indirectly nudging you to get rid of your older Apple products and buy their new ones. For example, let's use a high level example. When you buy an iPhone, the camera will never change. The camera features and picture quality will be the exact same on day 365 as on day 1.

Apple as a company is set up to only build and focus on software for newer hardware. They don't spend one minute extra to optimize for older hardware.