According to a new rumour from iPhoneSoft when iOS 16 comes out next year, it could drop support for some older iPad and iPhone models, such as the iPhone 6s, 6s Plus and the iPhone SE. Those phones are currently the oldest ones supported by iOS 15 and they have been for a number of years at this stage so this rumour isn’t very far fetched.
The rumour also suggests that the iPadOS 16 could drop support for similarly aged iPad models, such as iPad mini 4, fifth generation iPad, iPad Air 2 and the iPad Pro from 2015. All of the mentioned devices run at least an A10 SoC.
However, this is just a rumour and Apple is expected like every year to announce iOS 16 and more at WWDC in June and then be released in September which is a long way away at this stage. For now, we shall see.