Doubt about the network IP address and the broadcast IP address of a network

The convention that 0 is reserved for unicast, and 255 for broadcast was superseded in the mid-1990s by the use of variable netmasks. Now the IPv4s at each end of the subnet serve no purpose and could just as easily be assigned.

Although there is no technical impediment, in many cases the "monastery cat" paradigm was chosen. In other words, it's better not to touch anything because you don't know if something will break. But more specifically, because it was less work to continue recycling the same bookstores from 40 years ago.