And CL14 used to be awful compared to DDR3(CL6), and so on and so forth. If you ignore all the advantages of DDR5 over 4, it's frequency, burst length and its 2x32 bit independent channels and only focus on latency, we might as well still be using DDR3, it had the lowest latency out of all DDR generations so far.
Yes, and Intel did that with their current gen. Would it be nice to have DDR4 support forever? Sure, I guess but it doesn't make sense to support it financially. DDR4 prices are only going to get higher from hereon out, and like I posted, there's not a significant enough difference between the two's prices to continue to support both.