It's not that Apple is particularly good at supporting older devices, it's that Android vendors are catastrophically bad across the board.
Apple tends to drop support when some hardware feature or limitation doesn't play well with the new OS. For instance, the iPhone 6 only has 1GB of RAM.
My Nokia 6 from 2017 is still receiving security updates. The update cycle switched from 1 month to every 3 months after the device reached the 3 year update guarantee but it's still acknowledgedby the manufacturer.
Nokia phones are in my opinion way too underrepresented on the market for the support they give.
Apple tends to drop support when some hardware feature or limitation doesn't play well with the new OS. For instance, the iPhone 6 only has 1GB of RAM.