There is another side to this, as well. If you look at how Samsung operates, their MO is "three steps forward, one step back.". Introducing a downgrade allows Samsung a few more years to "improve" over the past product.
Another example are phones like the a52s, and the a82/Quantum 2. The a53 and Quantum 3 released a year later were a step back. The CPU, screen, and cameras were a downgrade. We are just now reaching most of the features that the -2 series had, with the -5 series midrange phones. My wife's a82/Quantum 2 still seems on par with what has been announced in the a55, with the exception of a larger battery and comms improvements.