networking – IPv4 Address Range Shortage Inquiry

Recently I was looking over RFC6890 (link here) to find out more about the current IP addressing schemes that are in place and noticed a rather large IP address range that is listed as “Reserved For Future Use”.

The IP address range in question is

Since IPv4 is currently running out of available address (hence the transition to IPv6) why wouldn’t the IETF open the range to the public so that it could be used as public IP address space? I know that it won’t solve the IPv4 limitations and I know that one day we will eventually run out however opening it to the public would give an additional 268,435,455 IP addresses which in my mind is a rather substantial amount that as of the moment is just sitting there doing nothing.

Is there any particular reason that it isn’t being used for public allocation?

A secondary question that I have is why is the loopback IP address range ( so large? As of right now (and I very much doubt it will ever change), the loopback IP address range is which is 16,777,216 IP addresses. What could we possibly need 16,777,216 loopback addresses for? If you have an answer for this could you please let me know?

Thank you.